When Matt Giteau came off the bench to make his Wallabies debut, he gave no thought to one day reaching the 100-Test milestone, he was only worried about the roasting he was expecting from coach Eddie Jones.

The then rising star of Australian rugby came off the bench at Twickenham with eight minutes to go in a 32-31 loss to England in 2012 and, in his own words, things didn’t go to plan.

“The one player I remember was Ben Cohen as he got the ball off the scrum and broke one of my tackles. You think of your mistakes and that’s the one that stands out,” Giteau said on Tuesday.

“At the time Eddie Jones had a score system where everything positive you did (earned) a point, anything negative you lost a point.

“I think I was the only player to finish a game on minus-four or something.”

Speaking ahead of Sunday’s World Cup quarter-final against Scotland, which will double as the 100th Test match for both he and captain Stephen Moore, Giteau marvelled at how things have changed in the 13 years since.

“After that game I never thought I’d get to 100, no way,” he admits.

“It’s obviously a very special week and I’m very grateful for the opportunities I’ve been given.

“(But) I didn’t think I’d get past one.

“Even to get one, though, is just as special.

“To be able to sing your national anthem and represent your family, your friends and your country, it’s very special.”

He will, on Sunday (Monday morning AEDT), line up alongside Moore as part of an extra-special milestone match.

Moore is hesitant to take too much of the focus off the fact Australia is playing for a place in the World Cup final four.

“I think for me it’s not really a week to be reflecting on things, we’ve got a great opportunity to play in a quarter-final of a World Cup and that’s more than enough to play for,” he said.

“So I don’t want the boys thinking about anything other than the opportunity we’ve got, preparing really well this week and playing our best rugby on the weekend because we’re going to need to do that against Scotland.

“Personal achievements are things you probably look at when you hang up the boots.

“Certainly that’s how I feel about it. It’s just as important as the last game and for me it’s no different to any of the other Test matches I’ve played.

“They all mean an enormous amount to me and this is the one that’s in front of us at the moment so it’s the most important.”