A 20-minute red card trial is one of three law changes to be trialled for the upcoming Guinness Pro14 Rainbow Cup.

As revealed by RTÉ Sport last month, the red card variation will come into effect from next weekend for the commencement of the new competition, along with captain's challenge and goal-line drop-outs.

The captain's challenge and drop-outs are already in use across Super Rugby Aotearoa and Super Rugby AU and their use has been encouraged by World Rugby to improve the game.

The red card replacement law allows teams to replace a player who receives a red card after 20 minutes with one of the substitutes.

The dismissed player would not be allowed to return, but it would mean that the deterrent of a serious foul play would be reduced with teams only reduced to 14 for 20 minutes - double the sanction given for a yellow card.

Players who have been substituted for tactical reasons may be used to replace a player who has received a red card. The usual replacement laws continue to apply in that a replaced player may return for an injured front rower, injury due to foul play, HIA or blood.

Teams will be allowed one captain’s challenge per match in relation to try-scoring and foul play incidents, or to challenge any refereeing decision in the last five minutes of a match.

Challenges can only be made up to 20 seconds after the referee has blown his whistle for a stoppage in play and only incidents from the last passage of play can be challenged.

The challenge will be referred to the TMO who will review the footage with the match referee making the final decision. If a challenge is successful, then the team keeps their challenge.

Prior to the 75-minute mark, the captain’s challenge can only be used to check for an infringement in the lead up to a try or to review foul play, but can be applied more broadly from the 75-minute mark in any match at which point the captain, provided they have not already lost their challenge, can use it to check any whistled decision regardless of whether a try has been scored.

Injury time is included in the post 75-minute period.

For held-up over the line, knock-ons that occur in goal or when the ball is grounded by a defending player in the in-goal area after a kick through, the defending team will take a drop-out from anywhere on the goal line.

The drop-out must be taken on or behind the defending team’s goal line and it must occur without delay and the ball must cut across the goal line and travel five metres. If this does not occur a sanction will apply and the non-kicking team may request the kick to be retaken or receive a 5m scrum in line with where the kick was taken.

Alan Gilpin, CEO of World Rugby, has welcomed the developments.

"We applaud Pro14 Rugby and the respective clubs for their enthusiasm to trial a number of law variations in the Rainbow Cup," he said.

"The addition of another top competition to the World Rugby law trials programme will provide invaluable data and feedback to determine future advances to game spectacle and player welfare."

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