Former Test referee Nigel Owens has squashed the idea of rugby using a 20-minute red card.
The idea is currently being trialled in the Super Rugby Pacific competition, where players who received a red card are not allowed to take any further part in the match, but they can be replaced after 20 minutes.
The thinking is that entire games of rugby can no longer be ruined by numerical advantages that come from early reds, but writing in his column for the Telegraph, Owens feared that the lesser sanction would "allow acts of thuggery to flourish".
"Personally, I feel the 20-minute red card is not a good idea," Owens wrote.
"If you want to create change in player behaviour and for coaches to change the way they coach tackle technique, then you have to stay firm with clamping down on strict punishments for contact to the head.
"Most people now abide by the speed limit. Imagine if you only had a £10 or £20 fine for going over the speed limit as opposed to three points on your license and a £100 fine – there would be a lot more people less concerned about being caught.
"The harsher punishment makes you really think twice. Those measures were brought in for safety on the roads, just as red cards in rugby are all about improving player safety."
Owens believes it is more important for World Rugby, and referees, to identify the infringements that do warrant a red card.
"Red cards should be for total acts of recklessness or thuggery – if you come running in from a distance with your arm by your side and your shoulder slams into the head or neck area of a defenceless player, for example. That is dangerous play," he wrote.
"Whereas if someone is very unlucky – you tried to make a legal tackle but the timing was wrong, or you try to clear someone out but you slip at the last minute or the player moves – then that player should not be sent off, because there are mitigating factors which make the contact accidental.
"The last thing the sport needs is a situation where a player runs in and headbutts an opponent in the opening minutes, only for the offender to then be replaced 20 minutes later by a substitute. In situations like that, your team does not deserve to go back to 15 players."