The Springbok number eight is winding down his international career but will hope it does not end on the French south coast with South Africa potentially needing a bonus-point victory to stay on course for a quarter-final place.
He moves from the back of the scrum to the side to bring added physicality to a loose trio that also includes Jasper Wiese and Siya Kolisi (32) against the powerful Tongan pack.
"There is not much difference at all, you are part of the back row," Vermeulen told reporters on Saturday. "It is not a big shift, just a change of number.
"I am looking forward to playing with Jasper, I have never played with him, only a little bit against him. I am looking forward to see how we pack down with Siya also starting."
As for the Boks’ performance against Tonga, Vermeulen says they realise it is a do-or-die clash.
"There are one or two small things we need to work on, but I can definitely say we have some juice left in the tank," he said. "We are going to have to do it tomorrow because there are no second chances."
The sight of Vermeulen in the coaching box for the Ireland game set tongues wagging that he may stay involved with the team beyond his playing days.
"It was crazy!" he said with a beaming smile. "They (team management) give players the opportunity to sit in coaches' meetings and some get the chance to sit in the coaching box to see how they view the game. You also bring a different perspective as a player.
"It is a nice dynamic; we learn a little bit and they (the coaches) see how we players think about the game going into the final five or 10 minutes. It is nice to be up there, daunting as well, but I had fun."
So does he see a role for himself in the Springbok set-up in the future?
"If you had asked me this a couple of years ago, I would probably have said no," Vermeulen admitted. "But when you finish (your playing career) you want to give back to the younger guys.
"If the opportunity arises, I would love to stay in the game. I love it and it is difficult to just step away when you have played professionally for 19 years."
