Koroibete scored two tries against the Springboks on Saturday evening (Sunday AEDT) after being elevated to the starting team in place of Henry Speight.

A star in the NRL, Koroibete could have spent the rest of his career in rugby league but decided to switch to the 15-man code last year before getting an invite on the spring tour to Europe.

With his former club Melbourne playing in the NRL grand final on Sunday against the North Queensland Cowboys, Koroibete wished his old teammates luck throughout the week but said he was happy with where he has ended up.

"It made me more hungry, knowing I had to earn my spot in the team and work hard," Koroibete said. "That's the mentality I had. Nothing about whether I had made the wrong decision. I just had to work to get in the team.

"There have been a few wingers there who have been better than me, so I just had to give it a crack and give it all I got for the Wallabies."

Koroibete has credited other Wallabies backs, notably five-eighth Bernard Foley, for setting up his tries, which gave Australia a chance of creating history in a country that has proven tough to win in.

"The boys are a hard-working side, so when the opportunity comes to score tries with the boys running out wide, all the credit goes back to the guys inside," Koroibete said. "I just didn't want to let the boys down and I went from there. Especially playing South Africa at altitude, it was going to be a big 80 minutes and there was no wing on the bench."

Coach Michael Cheika said Koroibete had a "standout performance" in what is perhaps a hint the speedster may remain in Australia's starting XV for their next clash with Argentina in Mendoza.

"I thought he played very well, he took his opportunities," Cheika said. "He had a couple of good scoring opportunities and he probably had an NRL tackle count in the first 20 minutes. He made about eight or nine. There's still a few things to work out positionally but he had a standout performance."

Inside-centre Kurtley Beale lauded Koroibete's form as "unbelievable".

"He's pretty deadly," Beale said. "I've always watched him playing league for the Storm and now to get the opportunity to play with him, you can see why he's such a dominant player. [He is] so strong with the ball in hand and defensively very, very strong.

"The boys are getting around him and helping him find his feet in the game. I certainly think there's a long way and a lot for him to give the game, that's for sure."