Rugby Scrum Laws Explained: Engagement, Feed and Penalties

The engagement call changed for the 2013-14 season, and it changed because of physics. Under the sequence that preceded it, two packs of eight came together from a standing start with nothing holding them, and the force of that hit was the thing everybody in the game had quietly worried about for two decades. Research commissioned around the problem, including biomechanical work carried out in England, established what most front-row forwards could have told you: if the props are already gripping each other before the packs engage, the collision loses a great deal of its violence and the scrum becomes something you can steer rather than something that detonates.

So the call became crouch, bind, set. World Rugby writes the law, Law 19 of the Laws of the Game, and the RFU applies it in England alongside its own domestic variations and a separate set of age-grade regulations that changes the scrum quite substantially for anyone under about sixteen.

What follows is the law as written and the law as refereed, which are not the same document. The gap between them at the scrum is wider than anywhere else in rugby union, and pretending otherwise makes a page like this useless.

When a scrum is awarded, and what put it there

A scrum is a restart. It is the way the game resumes after an infringement that is not serious enough for a penalty, or after a phase that has become unplayable, and the interesting part is not that a scrum happens but who gets to throw the ball in.

The knock-on and the throw forward are the two everybody knows: the non-offending side gets the put-in, at the place the ball went forward. Beyond those, the allocation follows a logic about who was making progress.

What happened	Who throws in
Knock-on or throw forward	The team that did not commit it
Ball unplayable at a ruck	The team that was moving forward before it became unplayable
Ball unplayable at a maul	The team not in possession when the maul began
Ball unplayable after a tackle	The attacking team
Ball held up in in-goal	The attacking team, five metres from the goal line
Kick-off fails to travel ten metres	The receiving team, who may choose a scrum on halfway
Team elects a scrum from a penalty or free kick	The team awarded the sanction
Accidental offside from which advantage was gained	The non-offending team

Two of those rows repay a second look. The ruck rule rewards momentum, which is why a defensive side that has driven an attacking ruck backwards can turn an unplayable ball into their own put-in, and why the referee's call of "who was going forward" is one of the harder judgements in the game. The maul rule works the other way and hands the throw-in to the defending side when a maul dies, which is the whole reason a maul defence sometimes chooses to bring one down legally rather than concede a try.

The mark for the scrum is where the offence occurred, but it is never closer than five metres to a touchline and never closer than five metres to a goal line. That five-metre minimum is why a knock-on right on the try line produces a scrum a good way out rather than on the whitewash, and it is a rule that has saved a great many defensive sides.

Where the offence is on or near the touchline, the scrum comes in the required distance, which changes the geometry entirely: a scrum five metres from touch gives the attacking side almost no room on the short side and enormous room on the open side, and that asymmetry is what half of the tactical planning around scrums is about.

Crouch, bind, set: what the referee is checking at each call

The referee marks the spot, both packs form up, and the front rows come to arm's length from each other with heads and shoulders no lower than their hips. Nothing has happened yet, and a great deal is already being assessed.

Crouch. Body height and squareness. A front row that crouches too low is preparing to go under the opposition, which produces a collapse. A front row that stands up is preparing to be driven backwards. The referee wants both rows level and both feet sets balanced, and this is where a well-drilled pack gains its first advantage: the side that is settled at "crouch" is the side that can react on "set".

Bind. Each prop now takes hold of the opponent. The loosehead binds with the left arm on the opposing tighthead, the tighthead with the right arm on the opposing loosehead, in both cases on the back or the side, grasping the jersey. The referee is looking at where that hand has landed. A bind on the arm, the sleeve, the collar or the armpit is an offence, and it is an offence for a reason rather than a technicality: a grip on the sleeve slips under load, the shoulder drops, and the neck takes the force that the shoulder should have taken.

Set. The packs come together. The referee is watching the timing, because engaging before the call is an offence, and the alignment, because a front row that comes in at an angle rather than straight is boring in from the moment of contact.

Then the scrum must be square and stationary before the ball comes in. That word "stationary" does a lot of work. A pack that is already driving before the feed has committed an early push, which is a free kick, and it happens constantly at every level because the incentive to steal a metre is enormous and the referee cannot see everything.

1. 1MarkReferee sets the spot, at least five metres from touch and five metres from the goal line.
2. 2CrouchBody height and squareness. Heads and shoulders no lower than hips, front rows at arm's length.
3. 3BindEach prop grips the opponent's back or side. A bind on the arm, sleeve, collar or armpit is illegal.
4. 4SetPacks engage. Early engagement, or coming in at an angle rather than straight, is an offence here.
5. 5Square and stationaryThe ball may not be thrown in until the scrum has settled. Pushing before the feed is a free kick.
6. 6FeedScrum-half throws in along the middle line without delay.

The referee's checkpoints at each call under Law 19. The words of the sequence have changed twice since the 2000s and the current form dates from the 2013-14 season.

Binding: props, hookers and the second row

The whole structure is a chain of grips, and every link is specified.

The loosehead prop, number 1, binds on the opposing tighthead with the left arm, outside and around the body, holding the jersey on the back or the side. The tighthead, number 3, does the mirror image with the right arm on the opposing loosehead. Neither may grip the chest, the arm, the sleeve, the collar or the armpit, and neither may pull an opponent downwards or exert force to make the scrum collapse.

The hooker binds with both arms, either over or under the arms of the two props, and stays bound.

The second row bind with each other and each bind onto a prop, with at least one arm around the prop's body. That bind is what stops the front row being a separate unit that can be pushed independently of the rest of the pack — it is the connection through which the shove is transmitted, and it is the first thing to go when a scrum is losing.

The flankers bind on a lock. The number 8 binds on both locks, or on a lock and a flanker, which is the only position in the scrum with a genuine choice about where to stand, and that choice is a tactical one about which side of the scrum the number 8 wants to be able to leave from.

All eight players must be bound before the ball is thrown in, and must stay bound until the scrum ends. A player who unbinds early has left the scrum, which affects both the structure and the offside law.

The formation itself is three, four and one. Three in the front row without exception — a scrum cannot be formed with two — four in the second, and the number 8 at the back. If a team is reduced in numbers, the scrum is reduced in a specified way, but the front row remains three.

Why the detail matters: the bind converts the front row from three individuals into one surface. A prop who is unbound, or bound in the wrong place, absorbs the drive through their own spine rather than through the pack. Almost every serious scrum injury in the game's records traces back to a structure that was not properly connected when the load arrived. Position numbers and their responsibilities are covered in our guide to rugby positions from 1 to 15.

The feed, the law and what referees actually allow

Here is the sentence that causes all the trouble. The scrum-half must throw the ball in straight, without delay, with a single forward movement, so that it lands immediately beyond the width of the nearer prop's shoulders. And the same law permits the scrum-half to align their shoulder on the middle line of the scrum.

Read those together and you have a legal stance that puts the scrum-half's body roughly a shoulder-width towards their own side, and a throw that is straight relative to the scrum-half but angled relative to the tunnel. That is the concession, it is in the book, and it is the reason a feed that looks flagrant on a television replay is often perfectly legal.

The sanction for a genuinely crooked feed is a free kick, not a penalty. Referees have been instructed to tighten this on several occasions, at both international and domestic level, and each tightening has held for a few months before drifting back. That drift is not laziness. A referee at a scrum is watching binds, body height, the near-side prop's angle and the far-side second row simultaneously, and the feed is the one thing they can least afford to be looking at when a scrum is about to go down.

The consequence is a game in which the hooker rarely strikes for the ball. The put-in team wins possession as a near-formality, the contest has moved from winning the ball to winning the push, and hooking as a skill has receded to the point where a genuine strike against the head is now a talking point rather than a routine event. Whether that is a loss depends on what you think a scrum is for. It is, at minimum, a real change to the game that no law revision has reversed.

Two further points on possession. The number 8 may pick the ball up from the feet of the second rows, and this is legal. Nobody else in the scrum may handle the ball at all — that is a penalty, not a free kick — and kicking the ball out of the scrum is likewise a penalty.

Once the ball is available at the number 8's feet and the referee calls "use it", the ball must be played away within five seconds. That call is the referee's way of preventing a dominant pack from simply sitting on the ball indefinitely, and it is one of the few timing obligations in the laws.

Offside lines at the scrum, including the scrum-half's

Two separate offside lines operate at a scrum, and confusing them is the most common misunderstanding among supporters.

For every player not in the scrum and not the scrum-half, the offside line is a line parallel to the goal line, five metres behind the hindmost foot of their own team's scrum. Not the middle of the scrum, not the ball — the hindmost foot of their own side, which moves as the scrum moves. If a pack is driven backwards, its backs must retreat with it. If the hindmost foot is less than five metres from the goal line, the offside line becomes the goal line itself.

That five-metre gap is what creates space for the attacking side and it is the single most valuable piece of geography a scrum produces. A pack that wins a scrum going forward pushes the opposition back line backwards with it.

The scrum-half is treated differently, because a scrum-half has to be able to reach the ball. The scrum-half whose team is throwing in may stand alongside the scrum and follow the ball. The scrum-half of the other team has two options and no third: stand with both feet behind the ball and close to the scrum on their own side, or retreat to the five-metre line with the rest of the backs. They may not cross the middle line of the tunnel, and they may not move round to the other side of the scrum while the ball is in it.

The line for the defending nine, in other words, is the ball itself. That is why a defending scrum-half shadowing the number 8 around the base is legal right up until the moment they step past the ball, and why refereeing that step is a matter of centimetres.

Offside lines end when the ball leaves the scrum. The wider law of offside, which behaves differently in open play and at rucks, is covered in our rugby offside law explainer.

Wheeling, collapsing and standing up

A scrum turns. Some of that is legitimate — one side pushing harder on one flank than the other will rotate the whole structure — and some of it is a deliberate tactic to disrupt the opposition or to manufacture a reset.

If the scrum wheels through more than ninety degrees, the referee stops play and orders another scrum. Which side then throws in has changed between versions of the law, and it is worth saying plainly that older supporters and younger ones will give you different answers because both were right at the time. Check the current law text for the season you are watching or refereeing.

Wheeling the scrum intentionally is a penalty. The word "intentionally" is doing something almost impossible there, because the referee is being asked to distinguish between a pack that is turning because one side is stronger and a pack that is turning because it has decided to. In practice the referee reads the feet: a front row stepping round rather than driving straight is wheeling on purpose.

Collapsing is the offence that matters most. A player must not intentionally collapse a scrum, and the sanction is a penalty; where the collapse is dangerous rather than merely cynical it becomes foul play and can carry a card. Pulling an opponent down, twisting, dipping under, and driving upwards to lift an opponent off their feet are all penalty offences on the same reasoning.

The awkward truth about collapses is that the player who ends up underneath is very often not the offender. A loosehead driven upwards and then dropped has been the victim of two offences in sequence, and the referee's job is to work out which of the eight players opposite initiated it, from outside a structure they cannot see into.

• 8Players per side
• 3Front-row players
• 5Backs offside line in metres
• 90Wheel limit in degrees

Figures set by Law 19 of the Laws of the Game rather than by competition regulation. Age-grade rugby in England varies several of them downwards.

Free kick or penalty: which offence gets which

The division is not arbitrary once you see the principle behind it. Offences that endanger a player or destroy the contest are penalties. Offences that merely spoil the restart are free kicks.

Offence	Sanction
Throwing the ball in not straight	Free kick
Throwing in before the scrum is square and stationary	Free kick
Delaying the throw-in	Free kick
Pushing before the ball is thrown in	Free kick
Front-row player raising a foot before the ball leaves the hands	Free kick
Intentionally collapsing the scrum	Penalty
Intentionally lifting an opponent off their feet	Penalty
Intentionally wheeling the scrum	Penalty
Binding on the arm, sleeve, collar, chest or armpit	Penalty
Rushing at opponents from a distance	Penalty
Handling the ball in the scrum	Penalty
Kicking the ball out of the scrum	Penalty

Treat that table as the current shape rather than as an eternal one. Individual offences have moved between the two categories across successive law revisions, and World Rugby has run global law trials that reclassified scrum sanctions temporarily before adopting or abandoning them. Anyone refereeing should be reading the law text for their season, and in England the RFU publishes domestic variations that apply on top of it.

The practical difference on the field is large. A free kick cannot be kicked at goal and cannot be kicked directly to touch for a lineout in your favour, so it is a restart with the advantage of possession. A penalty is three points if you are close enough, or a lineout deep in the opposition twenty-two if you are not. A dominant scrum that earns penalties is a scoring weapon. A dominant scrum that earns free kicks is an inconvenience.

Repeated infringement is its own offence. A pack that concedes scrum penalty after scrum penalty will be warned, and then a player — usually a prop, sometimes the captain — goes to the bin for the team. That is a management tool rather than a judgement about which individual offended, and it is the referee's only real lever against a pack that has decided the penalties are worth it.

Uncontested scrums and how a match carries on

Uncontested scrums look like a scrum and function as a formality. The two packs come together without contest, neither side pushes, neither side may drive the other from the mark, and the team throwing in must win the ball. Play then continues normally.

They are ordered on safety grounds, and only on safety grounds, when a team cannot field three suitably trained front-row players. That happens after injuries, after a red card to a prop or hooker, and sometimes during a sin-binning.

The mechanism for a card is set out in Law 3. Where a front-row player is sent off or temporarily suspended, the team may bring on a trained front-row replacement, and to do so it nominates another player to leave the field so the numbers stay correct. A side reduced to fourteen by a card involving a prop can therefore end up with a different fourteen than the one you expected.

Uncontested scrums remove an entire dimension from a match, and they remove it disproportionately from whichever side was winning that dimension. This has produced a long-standing suspicion, aired at every level of the English game, that a beaten pack is occasionally not as short of front-row cover as it claims. The response is procedural: match officials report uncontested scrums, competitions review them, and clubs are required to account for the circumstances. It is not a satisfying answer, and no better one has been found.

1. 1Injury or cardA prop or hooker cannot continue and the bench has no suitably trained replacement.
2. 2Referee's decisionThe referee, not the captains, determines that scrums must become uncontested.
3. 3Player numbersWhere a card caused it, the team nominates a player to leave so a trained front-rower can come on.
4. 4Uncontested playNo push, no contest, and the team throwing in must win the ball. Play otherwise continues.
5. 5AfterwardsOfficials report the uncontested scrums and the competition reviews the circumstances.

The sequence under Law 3 and Law 19. Competition regulations in England add reporting requirements and may affect player numbers.

Note that this is rugby union. The thirteen-a-side code handles its own scrums on a completely different basis, with six players a side and a contest that has been vestigial for decades — see our separate guide to scrums in rugby league, which is governed by the RFL and has no overlap with anything on this page.

Front-row cover and the twenty-three-player squad rule

The squad rules exist to make uncontested scrums rare, and they work by forcing selection to carry redundancy.

A team naming a twenty-three-player matchday squad must include six players able to play in the front row, with cover across loosehead, hooker and tighthead. Six from twenty-three is a substantial share of a bench, and it is the constraint that shapes every English club's replacement planning. Smaller squads carry proportionally lower requirements, set out in Law 3 by squad size.

The phrase the law uses is "suitably trained and experienced", and that is a certification obligation rather than a statement about willingness. A back-row forward who has scrummaged at training a few times does not qualify, and the responsibility for saying who does sits with the club and, in England, within the RFU's framework for front-row training and registration.

What this produces on a bench is a specific kind of arithmetic. A hooker who cannot prop is one body covering one position. A prop who can play both sides — a genuine loosehead and tighthead — is worth two. Clubs pay for that flexibility because it buys a bench place back, and the players who have it tend to have long careers.

It also constrains the fashionable bench splits. A side wanting six forwards and two backs among its replacements still has to satisfy the front-row requirement first, and the two backs then have to cover every position behind the scrum between them, which is why a utility back who can play scrum-half and full-back is such a valuable squad member.

The tactical use of front-row replacements has changed the shape of matches. Fresh props arriving around the hour mark against a tiring front row is now a deliberate plan rather than an injury response, and the scrum in the final quarter frequently looks nothing like the scrum in the first. That is a selection strategy the law permits rather than an accident, and it is worth watching for. How replacements interact with cards is covered in our guide to red cards and replacements.

Age-grade scrums in England and the safety reasoning

RFU Regulation 15 governs age-grade rugby in England, and it treats the scrum as a skill to be built rather than a contest to be introduced whole.

The youngest players do not scrummage at all. Tag rugby has no scrum, because it has no contact. Contact is introduced gradually thereafter, and the scrum arrives as a small, uncontested formation with a limited number of players and no push, growing towards the full eight-player contested scrum across several age bands.

Three restrictions run through the age-grade model. The push is capped — the figure of one and a half metres has been associated with the age-grade scrum for many years. The permitted wheel is tighter than the adult ninety degrees. And in the younger contested bands the strike for the ball is restricted or removed, so that the scrum is a means of restarting play rather than a means of winning it.

Regulation 15 has been revised more than once, and the precise age at which each step applies has moved. Do not take a figure from an old handbook, a coaching course you did some years ago, or a page like this one. Read the current regulation, which the RFU publishes and updates.

The reasoning is about the cervical spine. Front-row play is the highest-risk position group in rugby union by a clear margin, the mechanism of the most serious injuries is compression and hyperflexion of the neck under load, and a young player's neck musculature is not developed enough to protect them from adult forces. Building technique first and adding load later is not caution for its own sake; it is the specific intervention the evidence supports.

There is a coaching consequence that clubs sometimes resist. A junior team with one good scrummaging pack can win a great many matches by drilling the scrum hard, and the regulations are designed to prevent exactly that, because the child on the wrong end of it is the one at risk. The broader age-grade framework is set out in our guide to RFU age grade rugby rules, and the entry routes into the game are covered in how to start playing rugby in England.

What a dominant scrum looks like, and what supporters misread

Watch the near-side prop's shoulders. That is the single most useful piece of advice available to a supporter trying to work out what has just happened at a scrum.

A loosehead being driven upwards is usually the sign of a tighthead who has got underneath and lifted, which is an offence against the loosehead. A loosehead whose shoulders have turned inwards is usually the sign of a tighthead boring across, which is also an offence. A loosehead who has dropped to a knee may have been pulled down, or may have gone down deliberately to avoid being driven backwards. The three look almost identical from row 40 and the referee is judging them from a metre away with a limited view.

The crowd's instinct — blame whoever is underneath — is wrong more often than it is right.

The TMO does not help here. The television match official protocol covers foul play, grounding, touch and the phases of play leading to a try; scrum technique is not within it. A scrum offence is refereed live by one person and cannot be reviewed, which is why the scrum is the least consistently officiated part of rugby union and why no amount of law rewriting has changed that. Our TMO explainer sets out what the protocol does cover.

Referees manage rather than adjudicate. There is usually a conversation with both front rows before the match and another after the first problem scrum, then a warning, then penalties, then a card for repeated infringement. A front row that engages with that process gets a longer rope than one that does not, and props know it.

The reward for scrum dominance is not the pushover try, which is rare. It is territory and points from penalties, and it is the psychological effect on a pack that knows the next scrum is coming. A side with a dominant scrum can afford to kick to the corner, concede the lineout, and wait — because the scrum will come back around and it will be worth three points.

For the other set-piece and the other contest for possession, see our guides to the lineout laws and the breakdown laws. More rugby writing sits in our rugby section.