Chiefs assistant coach Tabai Matson speaks from experience when he says World Rugby's new tackle laws may result in an increase in head injuries.
The sport's governing body announced they will trial two new tackle laws at the upcoming U20 Championship and U20 Trophy tournaments in a bid to reduce concussion-related incidents.
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The laws lower the acceptable height of a tackle to "below the nipple line", and additional punishments for transgressors will be implemented.
A high tackle warning will be issued if the tackler does not bend at the waist when tackling and there is clear and obvious head contact for either player.
Speaking to Andrew Gourdie and Jim Kayes on RadioLIVE, Matson pointed to his time with Bath as an example of the laws not being effective.
"Last year I coached in the English Premiership, they changed the law halfway through the year and what ended up happening is there was a massive spite of head injuries," he said.
"When you're getting players to tackle lower, it's actually counter-intuitive. For the ball-carrier, you're not having your head threatened - we all want that, but actually it's the tacklers getting knocked out because they're having to get lower and lower.
"It takes a long time to change the patterning to people's tackle - I think you'll find it's actually counter-intuitive, there's maybe more HIAs (head injury assessments) from the tackle height.
"Are people going to coach players to lead with their head as they ball carry to try and get more penalties? It's a can of worms, but we'll see how it goes."
Matson believes World Rugby's findings on how successful the trial was in the Premiership are not entirely accurate, and hopes if the law makes its way over to Super Rugby that there's consistency.
"They will look at things like penalties for high tackles and things like that, and maybe in the Premiership across all games with the season just finishing, maybe that's been really successful, maybe they haven't had as many high shots from people tackling - but go back and look at the HIA spikes and see actually where the risk is now.
"What we're looking for is just consistency around what the picture looks like in the game, because often with a law change like that, there's a massive spike in penalties and yellow cards and then it kind of evens out about three or four weeks later.
"So as long as everyone is clear on the way they're going to rule that, happy days."
Listen to the full interview with Tabai Matson above.
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