Mitchell had been sidelined since round five with a hamstring problem but returned for the Rabbitohs in an assured 30-12 win over Parramatta on Saturday.

Immediately after the game Mitchell said he wouldn't be accepting a call-up from NSW coach Brad Fittler.

The Blues coach, who must name his side on Monday, now has to choose between sticking with Stephen Crichton and Matt Burton in the centres or recalling Jack Wighton to the starting side after he missed game two with COVID-19.

The Blues are aiming to win a series decider in Brisbane for the first time since Johns spurred NSW to victory back in 2005.

But the 23-game NSW playmaker said Mitchell had shown maturity by focusing his attention on Souths.

"Selfless, it's great stuff from Latrell," Johns told the Network Nine's Sunday Footy Show.

"You could see he's supporting the Blues, supporting Burton and Crichton.

"I think it's a really selfless decision and it was really mature of him.

"There would have been a lot of pressure today on not only Brad Fittler, but people within the team, about Latrell, whether he was going to be picked or not."

Johns tipped Wighton to return on the bench at the expense of Siosifa Talakai.

Mitchell also earned praise from his South Sydney teammates for putting the club first after more than two months on the sidelines.

Blues hooker Damien Cook is aware of Mitchell's unique talents but understood the fullback's decision to withdraw from Origin III.

"I'm really proud of him," said Cook. "All the work he's done the last 12 weeks to get himself right and now to put South Sydney first, it's great work from him."

"It makes Freddy's decision a lot easier I'm sure. (Burton and Crichton) did a great job in the last game."

Mitchell was solid in his first outing as he got through 80 minutes for the Bunnies.

They will need him firing if they are to advance up the ladder - Souths currently sit seventh - and lock in a finals spot.

"It shows a fair commitment from him to his teammates and to his club that he wants to perform here," said Rabbitohs coach Jason Demetriou.

"It shows a bit of respect to the Blues as well; after a great performance (in game two), he's confident that those guys can get the job done.

"He's in better shape than he was in round two when he came back (from suspension).

"He's coming back in round 16 when every bloke out there has played half a season. They're battle-hardened and they're a lot fitter and used to the game.

"For him to come back and see out the 80 was pretty good."

Australian Associated Press