Australian coach Darren Lehmann is unsure where Jake Lehmann sits in the thoughts of national selectors, saying he's unwilling to have the conversation with chairman of selectors Rod Marsh.

Lehmann has proven he is not afraid to make tough selection calls but his son is one topic the no-nonsense operator will refuse to broach with the selection panel as they settle on a squad for the third Test against South Africa.

Jake Lehmann is among the young batsmen around the country hoping for a call-up this week as Marsh mulls changes to the side embarrassed by the Proteas in Hobart.

Jake Lehmann: fast facts Age: 24

Age: 24 First-class games: 18

First-class games: 18 First-class batting average: 48.96

First-class batting average: 48.96 Top score: 205

Top score: 205 Teams: South Australia, Adelaide Strikers, Yorkshire

Jake Lehmann, who averages 48.96 at first-class level and represented Australia A earlier this year, is not expected to be called up for the day-night Test at his home ground, Adelaide Oval.

But if the left-hander continues to produce more knocks like the unbeaten 129 he recently scored against Tasmania, and Australia's middle order continues to misfire, then that moment could come soon.

Darren Lehmann insists he has no idea what fellow selectors Rod Marsh, Mark Waugh and Trevor Hohns think about his son.

"I don't sit in on anything when they (selectors) talk about Jake," he said.

"I don't know what they're saying about Jake.

"Not involved, and I'd be that nervous anyway I probably wouldn't be coach, I'd probably just go to the bar."

'Time for talking is done': Lehmann

Steven Smith and Darren Lehmann face a host of personnel changes after Australia's woeful Test form. ( Getty Images: Ryan Pierse )

Australia's incumbent Test XI, minus pacemen Mitchell Starc, Josh Hazlewood and Joe Mennie, have been sent back to the Sheffield Shield in an effort to rediscover form before the third Test starts next Thursday.

Selectors are expected to name a squad on Sunday, with Darren Lehmann guaranteeing it won't be an unchanged XI after five consecutive Test losses.

Adam Voges and Callum Ferguson appear the players at greatest risk of being axed, with Lehmann imploring his charges to start producing runs instead of words.

"We've talked a lot over the last few weeks, we talked a lot in Sri Lanka, and we talked a lot in South Africa. The time for talking is probably done," Lehmann said.

"We've actually got to make sure we're doing it on the ground. They prepare well, they're great trainers, they know what they need to do. It's now actually executing your plans on the ground."

AAP