Offside lines at the breakdown.

Where the offside line is

In rugby union, a ruck or maul creates offside lines for both teams. Those lines run parallel to the try lines and sit at the back of each team's side of the contest.

• At a ruck: the offside line runs through the hindmost point of any player taking part in the ruck.
• At a maul: the offside line runs through the hindmost foot of the maul participant nearest to that team's own try line.
• Near the try line: if that back point is on or behind a team's try line, the try line is effectively that team's offside line.
• For non-participants: players outside the ruck or maul must stay behind their line until the ball is clearly out or the phase legally ends.

How it works at a ruck

A ruck forms when players from both teams are on their feet, in contact, and over the ball on the ground. From that moment, arriving players must come from their own side and players already outside the ruck must not creep beyond the offside line.

• A defender beside the ruck cannot stand in front of the back foot and wait for the pass.
• A player may counter-ruck only by entering legally from behind the offside line and staying on their feet.
• A player who was offside must retire immediately and cannot block, tackle, or play the ball until put onside.
• The ball being visible at the back of the ruck is not always enough; referees look for it to be clearly out of the contest.

How it works at a maul

A maul forms when the ball-carrier is held by an opponent and a team-mate binds onto the ball-carrier while the ball remains off the ground. The offside line then follows the back foot of the maul for each team.

• Players joining a maul must do so from an onside position and bind legally.
• A player who detaches and moves around the side can become offside if they rejoin or interfere from in front of the offside line.
• Defenders may drive the maul legally, but they cannot swim around the side to the ball-carrier from an offside position.
• Attackers in front of the ball-carrier can also be penalised if they obstruct defenders or prevent a fair contest.

How officials read it

1. Identify whether the phase is a tackle only, a ruck, or a maul.
2. Set each team's offside line at the correct back edge of the contest.
3. Check whether arriving players entered from their own side and bound or drove legally.
4. Watch defenders outside the contest for early movement beyond the offside line.
5. Decide whether the ball is still in the ruck or maul, clearly out, or unplayable.
6. Penalise players who gain an advantage by being offside, joining from the side, or interfering before they are entitled to play.

When the line disappears

The ruck or maul offside line lasts only while that phase exists. Once the ball is clearly out, players may move up from open play positions, subject to the normal offside rules.

That is why many disputes turn on timing. If the scrum-half has only placed hands on the ball while it is still in the ruck, defenders usually cannot cross the offside line. If the ball has been lifted or moved clear of the ruck, the breakdown offside line no longer protects the passer in the same way.

What fans often miss

• "The ball was visible": visible does not automatically mean out. It must be clearly available away from the ruck or maul.
• "He came through the middle": coming through is legal only if the player entered from an onside position and stayed legal through the contest.
• "The defender was quick": quick line speed is allowed after the ball is out, but early movement from in front of the offside line is not.
• "Only defenders can be offside": attackers can also offend, especially by joining ahead of the ball, obstructing, or staying in front of a maul.
• "A tackle has the same line as a ruck": tackle-area duties and offside can be similar in practice, but the law analysis changes once a ruck has formed.

What the referee usually calls

Officials often manage the area with short calls such as "ruck," "maul," "back foot," "leave it," or "use it." Those calls do not create the law by themselves, but they tell players how the referee is reading the phase in real time.

Common penalties include offside at the ruck, side entry, joining the maul from an offside position, tackling the passer before the ball is out, blocking defenders from in front of the ball, and interfering after failing to retire. If the non-offending team can still gain a clear benefit, the referee may play advantage before returning for the penalty.

What this page covers

This explainer covers rugby union rucks and mauls under the World Rugby law structure. Domestic competitions may add referee directives, review protocols, or emphasis points, but the basic idea is stable: the contest creates offside lines, players must enter from their own side, and the line remains until the ball is out or the phase ends.

Next rugby topics

• Rucks and mauls
• Advantage
• Scrums and resets
• Lineouts and knock-ons
• Back to rugby overview

Source material

• World Rugby Laws of the Game
• World Rugby Passport: Law 15
• World Rugby Passport: Law 16
• World Rugby Beginner's Guide: Offside