Goalkeepers

Goalkeeper Tactics

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Jeff, a U13 – U19 referee, asks:

When the goalkeeper is challenging for possession of the ball, are there restrictions on bringing his/her knee up when they are jumping to grab the ball?

Answer

No … and yes.  Perhaps not a very helpful response so let’s explore below the surface.

Can goalkeepers raise their knee during the process of gaining possession of the ball?  We know, that’s not exactly how the question was posed … stay tuned.  Of course, why not?  Add in the phrase “while challenging for the ball” and there is now a significant dimension that has been added; namely, the presence of someone else (an opponent, presumably) who is also attempting to gain possession of the ball.  The big difference, of course, between these two — the goalkeeper and the opponent — is that one can legally handle the ball inside his/her own penalty area but the other one cannot.  Put them both outside the penalty area and they are on exactly the same level, at least legally.

So, let’s assume we are talking about all this happening inside the goalkeeper’s penalty area.  We can tell you that virtually all goalkeeper camps and trainers include the “raising the knee tactic” in their programs.  These camp trainers also provide (by example and implication — wink, wink) two standard explanations that they encourage goalkeepers to use if asked : to protect themselves or to gain height while reaching upwards for a ball.  Actually, the reason is very simple.  It is to help create a space around the goalkeeper into which it is dangerous for the opponent to enter, thus encouraging opponents to stay back to avoid being contacted by the raised knee.    By the way,  we encourage doubters to simply visualize approximately where that knee winds up when raised.  In short, it is done to intimidate.

Would we as referees look askance at field players raising knees to intimidate opponents who might wish to challenge for possession of the ball?  Would we perhaps be inclined to punish a player at midfield trying for a descending high ball who raised a knee to back an opponent off?  If “I’m just protecting myself” is good enough for the goalkeeper, why not for any other player elsewhere on the field?  The answer, unfortunately, is that this has become one of those “urban legend” things that got started long ago and has become ordinary in the minds of many officials who haven’t thought more deeply about why this behavior occurs.  Further, it involves goalkeepers who continue to benefit from their favored status as “special.”  We like goalkeepers — they are brave, interesting, funny, and as egotistical as anyone with a whistle, but sometimes this can be carried to extremes.

Accordingly, what this issue boils down to is not the fact of a knee being raised but why it is being raised.  Seriously, think back over the many games you have officiated and ask yourself how often you have seen a goalkeeper raise his/her knee when there is no opponent around.   Actually, if you do see this, more often than not the goalkeeper is trying to establish it as a routine action so you will be less likely to question it when they do it for the real reason.

So, keep a close eye on such encounters.  Obviously, if the knee is raised to intimidate and contact is made, don’t be so ready to give the goalkeeper a free pass.…

Definitions

Shielding the Ball

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Erich, an adult amateur player, asks:

Throughout the game I am writing about, the other team would “shield” us off the ball (which as an experienced player I am fine with and do myself): however, rather than attempt to maintain control of the ball within a playable distance they were initiating contact with our players, often by backing up away from the ball or to their sides specifically to initiate the contact. This was often accomplished with substantial physicality, to the point that several of our players were repeatedly knocked down throughout the game while attempting to go around opposing players or to defend them. It was never called because the referee judged the ball to be within a playable distance (which he arbitrarily defined as 3 feet, which I know is not the rule and is not part of my question).

The question is essentially this: at what point does “shielding” with the ball near enough to be controlled become a foul? Does it matter that the player be actually trying to control the ball? If you are at least nominally controlling the ball, can you just back over a defender rather than trying to go around him/her?

Answer

We know you said this is not part of your question but we feel compelled to point out that, currently, there is an official, lawful, and therefore controlling definition of “playing distance” … and it is not 3 feet.  For the first time ever, the International Board has provided a clear statement on this subject which applies, actually, to a several different scenarios in soccer, of which “shielding” is only one of them: it is the “Distance to the ball which allows a player to touch the ball by extending the foot/leg or jumping or, for goalkeepers, jumping with arms extended. Distance depends on the physical size of the player”.  There you have it.

Now, as for “shielding,” let’s return to the Law (as we always should when starting on the path to enlightenment), and we find the following in Law 12: “A player may shield the ball by taking a position between an opponent and the ball if the ball is within playing distance and the opponent is not held off with the arms or body. If the ball is within playing distance, the player may be fairly charged by an opponent.”  While we might wish that this would answer everything, it doesn’t.

Your scenario is a dynamic situation that often occurs a yard or so inside the field and is performed usually for the purpose of allowing or preventing the ball from leaving the field depending on which team would gain the restart.  Shielding can be either a defensive or attacking team tactic.  The dynamic can become particularly intense the smaller the field space is available for ball movement and the greater the number of players being shielded.  These factors are important to keep in mind because they help us understand why players do what they do.

Two critical issues are raised by the Law’s language.  First, while a shielding tactic may start with the ball within playing distance, it must continue to be in playing distance for the shielding action to continue to be legal.  If the ball is allowed to move beyond the defined distance or if the shielding action moves sufficiently away from the defined distance, the shielding itself becomes impeding an opponent (assuming no physical contact).  Second, even while still within playing distance, the otherwise legal shielding action can become converted to a foul by either the shielder or the opponent being shielded.  The shielding player could extend an arm to prevent an opponent from getting around the shielder’s body and thus commit the foul of holding if contact is made (the same would be true of extending a leg sideways to achieve the same result).  An opponent, who remains allowed to perform a legal challenge against the shielder, must not allow the challenge to become illegal in any way — for example by using excessive force or by using any force to make contact with the shielder’s back.

Most of this is generally clear, understood, and accepted.  Where we find the greatest debate is when the shielder, instead of standing solidly, attempts to push backward with the shielder’s back against the opponent, thus making contact.  While the intent is clear (to gain more distance to maneuver), the end result is usually an offense.

Simple contact is often made between opposing players due solely to inertia, and the innocence of the contact is shared by both players.  When such contact proceeds to include pushing (forcefully using the body to displace another player), we are into foul territory and guilt falls on the player who initiates, not the contact, but the forceful displacement.  If the shielder moves back to displace the opponent, the shielder must be called for pushing.  Likewise, if the opponent moves forward to displace the shielder, the opponent must be called for pushing.  And if the shielder moves far enough backward in an attempt to make contact (forceful or not) but the opponent evades and this results in the shielder moving beyond “playing distance,” the shielder must be called for impeding.  Pushing, of course, is a direct free kick foul whereas impeding is an indirect free kick foul (in the given scenario involving no contact). And if there is force which is deemed reckless or excessive, there must be a card.

It need hardly be added that deciding what happening in a shielding situation calls for close observation by the Referee and/or the closest AR.…

Law 4 - Equipment

A Cool Drink of Water

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Abdikadar, an adult amateur player, asks:

First, would there be a caution for a player to stand by the touchline and request water to drink though the match continues?
Second, in continuation of the above same question, what if he or she did the same by clearing a ball when he or she was holding a bottle of water in their hand?

Answer

First, could there be a caution?  Yes, potentially but there would have to be special circumstances.  Otherwise, no. This is an entirely ordinary action and is not considered misconduct.  However, technically, the player should make sure that he or she does not actually leave the field as this would be potentially cautionable.  Further, there is an express prohibition against throwing water containers onto the field (even at a stoppage!) and against players throwing water containers from the field in return.

Second. although we’ve never actually seen a player carrying a water bottle while actively engaged in play, it should be fairly obvious that this would not be permitted because the water bottle would be considered, in essence, illegal equipment.  It would be far better for a player at the sideline drinking water who feels the overpowering need to suddenly engage in active play to quickly return the bottle to someone or someplace off the field before rejoining the game.…

2016 and Later Law Changes

Stopping for an Injury

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Brian, a U-12 and under Referee, asks:

During a youth game (U-8 or U-9), there is a stoppage for an injury. The coach comes on to check on the player.  Since the coach entered the field to help the player, does that player need to step off the field before play resumes?  I know at older levels, this is the case, but am curious about at the younger levels.

Answer

Actually, some of your question assumptions are incorrect.  Under the Law, an injured player must leave the field if play has been stopped due solely to an injury.  It has nothing directly to do with the coach coming onto the field because, under the Law, the coach cannot enter the field without the express permission of the referee and no referee is going to give that permission until and unless play had already been stopped.  Some referees read the Law “sideways” and forget that the Law is expected to be understood as a whole, not in pieces.  So, the fact that the referee has stopped play solely due to an injury means by definition that the injury is serious because only serious injuries can be the basis for stopping play.

Where things get a bit complicated is if the referee stops play for some other reason (e.g., a foul) and then determines that a serious injury occurring during the stoppage or as a result of the foul that caused the stoppage in the first place.  Then and only then does the referee call for the entry of a team official (coach, trainer, etc.) – which, also as a result, requires that the player leave the field.  There are certain exception to this “must leave the field” requirement – e.g., the injured player is a goalkeeper, the player was injured in a “common collision” with a teammate, the injury was so severe that the player cannot be safely moved, or the injury was caused by a foul for which a caution or red card was given.

And we would never say that “the coach comes on to check the player” because you have already performed such a “check” and thus the coach does not.  There are no circumstances under which a coach can decide whether or not a player is to leave the field if the referee has (a) stopped play solely for the injury or (b) waved the coach onto the field for an injury caused by an opponent’s foul.  The player must leave according to the Law.  The only time a coach has any “say” in whether the player leaves or not is if the injury has occurred under circumstances where the Law itself does not require the player to leave (e.g., the goalkeeper was injured).  In short, if the Law says the player has to go, the player goes.  If the Law says that the player doesn’t have to go, the player doesn’t have to go unless the coach/trainer/parent wants the player to go.

Everything said above applies to all age groups, not just for U-littles.  The only decision in which the age of the player is relevant is your decision as to what constitutes a serious injury in the first place.  Once that decision is made, all the rest of it happens strictly in accordance with the Laws of the Game — neither you nor the coach (or anyone else) has any subsequent say in it.  This is one of the reasons why we train officials from entry level upward that, if play is stopped solely because an injury has been determined by you to be serious or if it is already clear to you at the moment of stoppage for a foul that the resulting injury is serious, your very first task after whistling for the stoppage is to wave someone from the injured player’s team (coach, trainer, etc.) onto the field — not to “assess the injury” because you have already done that, but to arrange for the safe removal of the player from the field (unless one of the exceptions applies).…

Safety!

Where Is the Danger?

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Daniel, an adult amateur fan, asks:

In the penalty area, a defender bends to head the ball at a low level in front of an opponent who tries to kick the ball towards the goal. The attacker hits with the foot the opponent’s head. How should the referee decide?

Answer

This is, technically, not a Law question but a Refereeing question.  And it is interesting (very helpful also) that you phrased it as “How should the Referee decide?” rather than “What should the Referee decide?”  The difference between these two questions is that the second question wants to know the end result whereas the first question wants to know what information is relevant to making the decision.

We can’t answer “what” the Referee should decide because this is one of those situations where “you had to be there” to know exactly what the Referee saw, what further advice from a different angle the assistant referees might be able to provide, and particularly what led up to the described event.  Accordingly, we will focus on certain generalizations about this sort of scenario that come from listening closely to experienced Referees and by our own direct experience over many years.

The standard “formula” is that, below the waist, feet are expected to play the ball and a head invading the area below the waist would normally be considered potentially dangerous.  Chests and heads are expected to play balls in the area above the waist and an opponent intruding a foot above the waist would normally be considered a dangerous action.  Without actual contact in either of these scenarios (i.e., foot on head below the waist) we could have no offense at all or, at most, a dangerous play offense if an opponent is unfairly prevented from playing for fear of engaging unsafely.  With contact, there is great likelihood of a direct free kick offense — an offense which, moreover, would hover in the “careless” or “excessive force” misconduct realm depending on the specific circumstances.  So, where the ball is clearly above the waist level, safe play presumes the use of chest and head but not feet, and the higher the ball is above waist level, the stronger is this conclusion.  The farther the ball is below the waist, the stronger is the conclusion that play should involve feet, not heads or chests.

That said, there are lots of “ifs” and “maybes” that must be considered.  For example (and probably the biggest “if”) is the waist area itself – that is a sort of “no man’s land” where either head or feet might be used and in either case could be considered dangerous and worth close attention.  Here, we normally advise the Referee to evaluate the potential for danger by looking at the issue of which player initiated the play on the ball.  If player A clearly began a movement which involved putting his head down to the area of the waist to make a play for the ball and, despite seeing this occur, player B (an opponent) nevertheless responds with starting to play the ball with a foot also at waist level, we would usually consider that player B has created the danger because player A in effect set the terms of the play and player B now has an affirmative responsibility to avoid raising his foot to the same level as player A’s head.  Similarly, if player A had clearly made the first move at a waist-high ball using his foot, player B would be considered the one causing danger by bringing his head down to the waist level as a countermeasure.

But even here, there are problems.  First, what if the two players’ movements, one with the foot and the other with the head but both at waist level, occurs simultaneously?  Second, what if one player is not positioned to see what the other player is doing?  Normally, we tend to not give the benefit of the doubt to players who operate on the “blind side” of an opponent.  Third, the goalkeeper is often a complicating factor since goalkeepers more routinely engage in play at lower body levels with their hands, which tend to be accompanied by their head.  This is something attackers know and are commonly expected to take into account.  Fourth, there is a slight bias in favor of a player who is initiating a play of the ball with the head because, once started, the developing position of the head tends to result in obscured vision regarding what the opponent might be in the process of doing … until it is too late.  Finally, in all this, the age, skill, and experience level of the players must be taken into account.

We cannot cite any Law in support of these generalizations — beyond “safety, fairness, enjoyment, and the display of skills” as the ultimate objectives for all officials.  They are part of the “lore” of officiating, developed over a long period of time in practical response to real-world player behavior, and passed down in Referee tents all across the world.…

"Inventive" Refs

Injuries, Fouls, and Misconduct

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Enos, a HS and college coach, asks:

What does the rule book say about the following situation in a HS Soccer game?

During the play, a defender player came in with a 50/50 slide tackle against an attacker with the ball.  The tackle looked bit hard.  The Referee issued a yellow card on the play and the whistle was blown.  Unfortunately, the attacker sustained an injury.  During the visit of the sideline coaches and trainer, it was determined that the injured player might have a broken leg. The Referee came to the sideline and issued an additional red card stating that she is changing a card due to injury.  Is that allowed or should the report be made where yellow card is recorded and explanation is added to the match report?  What would be suspension in that case?

Answer

First and foremost, readers may recall from the information under the “About” tab above that our primary focus is on the Laws of the Game.  While we are fairly familiar with such other rules as those used  by NFHS and NCAA, we avoid interpreting them or offering guidelines about their implementation except where their meaning is crystal clear.  Accordingly, for the most part, we will treat this question as though the scenario occurred in a match controlled by the Laws of the Game.  Perhaps, later, if we are feeling frisky, we might branch off briefly into high school play.

Also, one minor observation — we hope that, in this scenario, the Referee had sufficient presence of mind to have whistled play stopped before actually issuing any card, no matter what it’s color.  We also wonder why the Referee felt it necessary to come to the sideline in order to change the card from yellow to red.

Anyway, two principles are in play here.  One is that the Referee has the authority to change a decision as to any matter (including, in fact, whether to have stopped play in the first place, though that leads then to the issue of how to restart play if this is the case) before play is restarted.  Accordingly, the Referee has a right (arguably even a responsibility) to change a decision in pursuit of more accurately implementing the Law upon private reflection or becoming aware of additional relevant information or receiving information from a member of the officiating team.  So, changing a card, by itself, is certainly permitted by all Law/rule sets.  Here, it was yellow to red but it could also have been red to yellow or to no card at all, or it could have involved removing the card from one player and charging a different player with misconduct.  There are only two misconduct-related changes that can occur even though play has restarted (we have dealt with them in other Q&As).

The other principle, however, is a bit more problematical.  We referred above to “relevant information” as the basis for changing a decision.  Suppose the Referee had announced that, upon reflection, she thought the defender should receive a red instead of a yellow card because his hair was red.  Does the Referee have the right to change the card?  Yes.  Is this information about hair color relevant?  No.  The seriousness of an injury is not a relevant fact.  Law 12 provides that, for each of seven specifically-named player actions, the Referee is to  decide the action is a direct free kick foul if the act was careless or reckless or if it was performed using excessive force.  Any one of these is sufficient to make the decision that it was a direct free kick foul.  As for the possibility that the action might also be misconduct, the Referee is advised in Law 12 that carelessness by itself does not involve misconduct, that recklessness by itself is cautionable, and that the user of excessive force should be sent off.  Nowhere here or in the subsequent explanations of each of these three critical terms is the word “injury” used.

Injuries can occur any time, caused by anyone or by no one, be the result of deliberate action or simple accident.  Even carelessness can result in an injury.  Furthermore, the seriousness of the injury is not, by itself, any indication of how to treat the action.  Clearly, the risk of serious injury increases with the use of excessive force, but a “serious injury result” does not make its cause a red card offense.  When the tackle occurred, the Referee’s job was to assess carelessness, recklessness, or the presence of excessive force.  None of these three things can be inferred by the subsequent decision that an injury was serious, just as the lack of a serious injury cannot infer that the action did not involve excessive force.  Neither can the presence of a serious injury be cited as proof that the safety of an opponent had therefore been endangered any more than the absence of a serious injury be offered as proof that no opponent had been endangered.  The seriousness of an injury is a function of the injury’s impact on the player, not a function — an element perhaps, but not a function — the Referee should take into account in deciding the color of a card.

In the given scenario, it would have been entirely appropriate (indeed, good officiating team communication) if, before play was restarted, an assistant referee had advised the Referee that the “50/50” tackle, in addition to being a “bit hard,” had come in uncontrolled from the attacker’s blind side, and with studs up.  Any of these factors, much less all of them, would have been clear-cut grounds for the Referee to decide that the caution should be changed to a red card.…

2016 and Later Law Changes

Hanky-Pank with KFTM

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Shawn,  a HS and College Referee, asks:

Have you ever had a kicks-from-the-mark situation where, in the execution phase, an eligible player became ineligible due to injury, misconduct, or other cause? How did you handle it?

According to LOTG, “the opposing team will not further ‘reduce to equate’” and “the team with fewer players may use all its eligible players before the other team and will therefore begin allowing its players to kick a second time before this occurs for the other team.” Also, KFTM “will continue so long as the team has at least a single eligible player”. This seems ripe for abuse, as, in a worst case scenario, a team whose keeper is also an excellent penalty kicker could declare all other eligible players “injured” once the execution phase has begun, or after the initial group of five have kicked. The guidance from expert referees is the referee should “reduce to equate,” using Law 18.

Answer

We can tell you how it used to be handled in the “good old days,” how that changed to the not-so-long-ago days, and how it is supposed to be handled as of June of this year.

First of all, take note that what follows your opening to the second paragraph below of “According to the LOTG” is out of date.  Second of all, the scenario you describe is always possible if there are bad intentions on the part of a team – the consequences may be in accordance with the LOTG and the Referee may have little recourse because nothing illegal is being done but the Referee can include in the match report the behavior of a team which is otherwise legal but offends the spirit of the game.

As of this year’s version of the LOTG, “reduce to equate” continues throughout the entire KFTM procedure, not just during the phase of the procedure that precedes the first kick.  The loss of an eligible player through injury or misconduct triggers a comparable reduction in the number of opposing players who are eligible.  The Law also specifies, though, that a player who chooses not to participate despite being eligible (i.e., not being declared injured or sent off for misconduct) is counted as having unsuccessfully kicked from the mark.

If the Referee believes that a team is apparently manipulating the availability of its eligible players in an unsporting manner, the solution resolves into two options.  First, if listed eligible players are being declared “injured” and unable to participate with no supporting evidence, then the solution is to proceed in regular order (i.e., following the rules) but then to report this information to the competition authority with full details in the match report.  Second, if after listed eligible players in any round have taken a kick but there remain other listed eligible players who, despite not having been sent off and not having been declared injured, do not respond to a call to take a kick, then after calling the name of a remaining eligible player several times without success, the Referee simply marks their “attempt” as a “miss” (i.e., no goal) and moves on in regular order.

Remember, the Referee does not choose who kicks — this information is supplied by the team at each kicking opportunity.  The Referee has four tasks: (1) signal for the kick to be taken, (2) observe if any misconduct occurs by the kicker or goalkeeper, (3) record the results, and (4) ensure that no eligible player from that team in that round takes a kick a second time in the same round.  The only way a player is removed from eligibility is to be sent off or declared injured and unable to participate, at which point the opposing team reduces its eligible play list accordingly and notifies the Referee which eligible player has been removed.…

Advantage

A Plethora of Cards

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Steve, an adult amateur fan, asks:

If a Referee plays advantage with the intention of going back to book the player once the play has stopped but that same player makes another tackle worthy of a yellow card in the same passage of play, can the Ref deliver 2 yellow cards and send the player off?

Answer

Absolutely  …  assuming the original misconduct was also a cautionable offense.   If it was a sending-off offense, however, then only the red card would be shown at the next stoppage with no following yellow card for the subsequent misconduct because, by tradition, no additional cards are ever shown following a red card.  Nevertheless, in this sort of situation, the additional misconduct (cautionable or sending-off) is included in the match report but clearly identified as conduct occurring after a red card.  Keep one thing in mind – the International Board has strongly recommended that, if a sending-off offense has indeed been committed, advantage should generally not be applied, particularly if the red card offense involved violence of any sort (e.g., serious foul play, violent conduct, or spitting).

Getting back to your original question, it is entirely possible, at the same stoppage, for the Referee to display a yellow card, then to reshow the yellow card, and then to display a red card – three cards at one time (they are still showed sequentially, not literally at the same time)!  Finally, in a case like this, the restart would be determined by the original offense, not by what happened afterward, during the “advantage time.”  The exception would be if, in the Referee’s opinion, the advantage had been fully realized: if so, the restart would be dictated by the second offense.…

2016 and Later Law Changes

Playing Distance (and Happy Holidays to Our Readers)

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Scott, an adult amateur Referee, asks:

Is there a distance from the ball when a referee should call an impeding foul instead of allowing the defender to “shield” the ball from the attacker. For instance, the ball is rolling quickly and is on a path to go out of bounds if no one touches it and there is an attacker running full speed towards the ball from a distance and the defender steps in 5 yards from where the ball is and shields the attacker so the ball will go out.

Answer

Good question and, as with many similar good questions, there isn’t a simple answer.  Fortunately, the answer became less complex in 2017 when the International Board published the 2017-2018 Laws of the Game.

At the core of your query is the concept of “playing distance” which arises in several different scenarios in soccer generally as well as in the Laws.  For example, it arises in Law 12 when the offense of “impeding the progress of an opponent” is discussed:

Impeding the progress of an opponent means moving into the opponent’s path to obstruct, block, slow down or force a change of direction when the ball is not within playing distance of either player. [emphasis added]

A bit later on in the same section of Law 12, your scenario is targeted:

A player may shield the ball by taking a position between an opponent and the ball if the ball is within playing distance and the opponent is not held off with the arms or body. If the ball is within playing distance, the player may be fairly charged by an opponent. [emphasis added]

Other places where the concept of “playing distance” arises include “interfering with an opponent” as one way of committing an offside violation, as one of the criteria for DOGSO (denying an obvious goal-scoring opportunity), and as one of the ways that a legal charge can become illegal.  Clearly, knowing what “playing distance” is and is not is an important element of refereeing.

Years ago, it was common for referees to treat “playing distance” as some absolute value – e.g. one or two yards or several steps – in all cases and circumstances.  More recently, the 2014 version of Advice to Referees on the Laws of the Game made the following observation:

The referee’s judgment of playing distance should be based on the player’s ability to play the ball, not upon any arbitrary standard such as a specific number of feet or steps a player is away from the ball. The decision as to whether a player is or is not within playing distance of the ball belongs solely to the referee.

In 2017, the International Board for the very first time provided an operational definition of the concept as follows:

Playing distance.  Distance to the ball which allows a player to touch the ball by extending the foot/leg or jumping or, for goalkeepers, jumping with arms extended. Distance depends on the physical size of the player

In essence, the now-official definition is completely consistent with USSF’s 2014 Advice to Referees that the concept has to be defined by the “player’s ability to play the ball” and adds the critical reminder that, even so, it has to depend on “the physical size of the player.”  Obviously, for most referees, this means that an average-sized U14 player will have a shorter playing distance than would an average-sized adult amateur player – all of which takes us back to what we said at the start of this answer and what Advice to Referees said in 2014, that decisions about playing distance belong solely to the Referee. What has changed (and improved) is that the International Board has now given us a “yardstick” for exercising this judgment – the distance between the ball and how far a player can stick his or her own, individually-sized leg out (or a goalkeeper can jump up or out while reaching for a ball in the air).…

Ball in Play

Soccer and Physics

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Ben, an adult amateur player, asks:

Why does the air pressure affect the distance the ball travels?

Answer

Interesting question – ready-made for an answer chock full of equations and lots of physics, but we’ll rein in our enthusiasm and try not to get technical.  The answer depends on what the ball is traveling on.

When the ball is in continuous contact with the surface of the pitch (i.e., it is rolling), the pressure of the ball determines the rigidity of the surface of the ball (higher pressure = more rigidity) which in turn has a measurable though not easily visible effect on the total surface area of the ball that is in actual contact with the ground’s surface.  At higher pressures, the area of contact is smaller (because the ball is “rounder”) and thus there is less friction on the passage of the ball across the pitch surface.  There is a smaller, secondary effect at higher pressure caused by a somewhat greater “lift” that makes the ball ride a bit higher on the pitch surface.  Remember, a ball is, in effect, a type of balloon – the more air there is in it, the lighter it is and, as with “roundness,” this reduces slightly the contact surface area.  In short, a higher pressure produces a speedier ball, all other things equal.

However, the other medium on which a ball travels is the air.  Here, again, air pressure acts similarly (see above).  A rounder ball (a function of air pressure)  encounters less “drag” while in the air and has greater buoyancy.  There is a third factor regarding a ball traveling in the air that is not found when a ball is rolling on the ground and that is the fact that, inevitably, a ball in the air comes down and makes contact with the ground.  Holding all other factors equal, a higher ball pressure makes for a higher bounce (a factor that you can often actually hear by listening to the sound of the contact – a ping rather than a thud in extreme cases!).  Now, however, something else comes into play (no pun intended) and that is the angle at which the ball is traveling just prior to contact with the ground.  It isn’t speed as such (as is the case with rolling) but it does directly affect distance – which, in a soccer game, may be just as important as the speed of the ball.  With higher air pressure comes greater bounce when the contact occurs – the more acute the angle, the greater the distance for any given air pressure as a result of the bounce effect.

So, the higher the pressure (within the range permitted by Law 2, of course), the greater is the rolling speed and the greater the rolling speed, the longer is the distance the ball will roll (assuming someone from the other team doesn’t stop it!).  This generalization also assumes a relatively constant consistency in the surface (one of the reasons why, again all other things equal, soccer balls travel faster on artificial surfaces relative to grass, and faster on short grass than taller grass).  Further, for a ball launched into the air, the higher the pressure is, the greater the distance traveled both before and after “the bounce” for contact at any angle of less than 90 degrees behind the ball (disregard all forms of spin … it gets too complicated).

There — not a single formal physics lecture and no equations!  Instinctively, though, a home team which has been coached to engage in fast play will likely provide the Referee with game balls at the upper end of the allowable pressure range.  A different team, which may not like or be used to fast play, is likely to provide game balls at the lower end of the pressure range.  It is not the Referee’s job to deliberately favor one team or another by changing an allowable ball pressure up or down based on personal preferences.  If it is in the allowable range, leave it alone.  If it is not, give it to the home team (it’s their ball anyway) for correction but be sure to check a corrected ball again and, again, leave it alone if it is in the allowable range.…