The Collins dictionary defines a ruck, in its rugby union context, as ‘a contest between the two packs of forwards to gain control of the ball when it is on the ground after a tackle’. If only it was as simple as that...

The ruck is arguably the most contentious areas of the sport with hundreds of them occurring every match. They’re highly important but incredibly complicated, providing a platform for multiple ways for penalties to be conceded.

A ruck starts when a player is tackled and the ball is on the ground – although they can be avoided if the ball is quickly picked up from the ground and passed away or carried forward, or if the tackled player pops to a teammate immediately or maybe after a half-roll on the deck.

The ruck starts when two players compete for the ball. The tackler can compete for the ball, but only when they have shown a clear release of the tackled player – failure to do so results in a penalty.

More often than not, it’s not the tackler who competes for the ball but a teammate who leans over to compete for the ball. They must stay on their feet doing this, else they will concede a penalty. That player competing, or ‘jackaling for the ball’, will then likely be hit or ‘cleared out’ by players from the attacking team, to provide clean ball for the next attack.

Related: What is the jackler?

One player from each team has to make contact while on their feet while the ball is on the ground and the two players are positioned over it for a ruck to be formed. There is one more criterion for a ruck to be formed. Both players must keep their heads and shoulders at the same level or above their hips.

Imaginary offside lines are drawn when one player from each team has made contact, using the hindmost foot of each side. Players must arrive through the gate (from behind) and not arrive horizontally. Coming in at the side is a penalty offence.

There’s many more ways of conceding penalties at a ruck. Players who arrive after the ruck has formed can’t make a grab for the ball and will be penalised for handling in the ruck.

A penalty can be awarded if players ruck over the ball and their hands are on the ground, so they are no longer supporting their own bodyweight. Collapsing a ruck is also illegal as is going off your feet when clearing out, although it’s rarely penalised in modern rugby.

It is also illegal to step over the tackled player and to kick the ball from a ruck. And while it was once common place at the breakdown, it’s also illegal to use your boots to stamp or ‘shoe’ for the ball if it has become trapped under bodies or a disruptive hand.

The ball is out of a ruck when it moves past the hindmost foot of the players who have formed or joined the ruck.

For further information on the laws of the game relating to rucks, consult World Rugby.

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