World Rugby is planning to run trials on red cards and examine tackle height in the elite game as part of moves to improve the sport’s safety and appeal.
It is also looking at ways to speed up the game as part of a new five-stage plan unveiled on Tuesday.
The governing body says it is focused on “enhancing ball in flow, reducing stoppages and increasing welfare”.
World Rugby chairman Sir Bill Beaumont said the measures would “excite the next generation of fans and players”.
“Change is in rugby’s DNA,” he added.
“That means being bold, embracing change by dialling up the entertainment value, making our stars more accessible and simplifying terminology and language used to explain rugby to those who are yet to fall in love with it.”
The first phase came into force on 19 March and sees minor changes to some laws of the game for speeding up play. The second phase similarly sees some changes aiding the speed of the game, and they will be considered by the World Rugby Council at its 9 May meeting.
Phase three will see trials adopted by unions in their domestic games “aimed at enhancing game continuity”. They include the expansion of the shot clock for scrum and line-outs and reduced kicking time.
But the proposed stage four could have the most impact on the sport. It will see specialist working groups set up to examine changes, including the results of the community tackle height trials across 11 unions and their “appropriateness for elite rugby”.
Rugby chiefs in England reduced the tackle height in the community game on 1 July 2023, with players only allowed to tackle from waist-height down.
Implementing the same measure in the elite game would represent a significant change in the sport, along with global plans to trial red card replacements.
In the new measures, a player who is sent off will not be allowed to return to the field but is replaced after 20 minutes, in an attempt to increase the competitiveness of matches.
It has already been tested in Super Rugby, while northern hemisphere countries are also becoming increasingly open to the idea after the last men’s and women’s World Cup finals ended with one team having 14 players on the field for the majority of the game.
The fifth and final stage will see World Rugby “test out new aspects of law in a controlled environment” which “have an impact on speed or safety”.
“These are likely to include the scrum engagement sequence and the tackle/ruck area,” it said.
