Four years ago, Wallabies forward Dean Mumm was certain he would never represent Australia again.

Having been out of the Wallabies’ selection mix for more than a year, Mumm made the tough decision to move overseas in 2012 to link up with English side Exeter.

It ended up being the best rugby decision he ever made.

Mumm’s three-year stint at Exeter left him refreshed and hungry for more.

And when the chance to rekindle his Wallabies career popped up, Mumm took it with both hands, rejoining the NSW Waratahs last year before ending his five-year Test hiatus shortly after.

Mumm will notch his 50th Test cap in Saturday night’s clash with Argentina in Perth, and he openly admits it’s a milestone he thought he would never achieve.

“When you decide to go way – particularly (given) the Giteau rule wasn’t in place – you basically had to give up any hope of playing for Australia again,” Mumm said.

“I went away, freshened up and got a different perspective on what it means to wear the Wallaby jumper.

“You get a real sense (that it’s) a really finite period of your life and a really finite opportunity and you’ve got to make the most of it.

“That’s what coming home for me was.”

Mumm’s Test return came against Argentina in Mendoza last year, with the 32-year-old coming off the bench to score a try in the 34-9 win.

“It was an alright try when you look back at it,” said Mumm, who shook off four tacklers to get to the line.

“It’d been a bloody long time since I’d played in a Test match, so I was just trying to make the most of it.

“You just want to try and get there. I’m not fussed how it happens, I don’t get over the line that often.”

Prop Tom Robertson and forward Lopeti Timani will make their Wallabies debuts off the bench against Argentina.