If Ireland are to beat France this weekend at the Aviva Stadium, then stopping Antoine Dupont - or at the very least slowing him down - will be vital to victory.
The Toulouse scrum half solidified his reputation as the best scrumhalf in the world - and possibly the best player in the world - with a sensational performance against Italy in round one, scoring a try and directly assisting four others in the 50-10 route in Rome.
Dupont terrorised Ireland when the sides met last Halloween, scoring a try and assisting another in the 35-27 win in Paris.
Yesterday his opposite number on the Ireland team Conor Murray spoke about how they need to balance their efforts in stopping Dupont, so as not to neglect the very many attacking threats in the French backline.
And on this week's Six Nations Show on OTB Sports, Johne Murphy and Alison Miller echoed those thoughts.
Murphy suggests that devising a gameplan just to negate Dupont's ability could be too big an ask at short notice, and Andy Farrell's side should prioritise limiting the scrumhalf's ability to influence the game.
"I think it's his anticipation as to where the ball is going to be. His vision around and his knowledge around the attacking system around who is going to break, when they break, and that potential, is massive. He is probably the best in the world at the moment, and he's consistently the best in the world.
"It's very hard to change up, to mark him, without potentially changing up your whole system. Particularly when you're looking at those support lines. Ireland have a 13-2 defensive system where they try to bring linespeed. You can look at changing and going to a 12-1-2 with someone in behind the ruck, trying to chase him on those support lines, a man marking job, but you're changing your whole system in a matter of three or four training sessions.
"It's really difficult to do but trying to swarm him in and around the ruck. If you have an opportunity to tackle him, tackle him. Make sure you're on your feet before he is, and all those little things do add up," Murphy says.
Former Ireland winger Alison Miller says creating as much slow traffic close to the ruck will be one way to limit his influence.
"France's attack - he is the lifeline of the French attack - and I think he's so important to their attack that everything comes through him. It's important that Ireland do try and nullify the threat that is Antoine Dupont.
"He's probably the best player in the world at the moment, he seems to be the full package, so I think - as Murray said - trying to slow down his ball, he thrives off quick ball. Our interior defence is going to really important because he'll look to snipe around the ruck. Our defensive integrity around the interior is going to be really important.
"We do need to suffocate him because if we can prevent him from getting to the ruck a second later, he's so good with support lines and trail lines, if we can put him on the ground and irritate him, and not let him get to those support lines, I think it's key. He's pivotal to their attack." she said.
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