New dad Christian Lealiifano will enter the Wallabies' camp in Brisbane as early as Wednesday night, adding further intrigue ahead of coach Michael Cheika's first Test team announcement.
But Wallabies great Tim Horan believes Lealiifano's decision to stay in Canberra for the birth of his first child might have cost him "the next few Test matches".
Brumbies co-captain Lealiifano was considered no chance of playing Saturday's three-Test series opener against England after missing every Wallabies session including last week's Sunshine Coast camp.
Even after his son's birth on Tuesday following a 10-day wait, Lealiifano was still expected to be asked to remain in Canberra.
However, inside centre hopeful Lealiifano will arrive in Brisbane as soon as Wednesday night - before Cheika's Wallaby team announcement on Thursday.
Lealiifano would only have two training sessions before the Suncorp Stadium clash if picked.
Horan believed Lealiifano could not be parachuted into the team.
"For the first Test match, you need to be there to understand the patterns of play and the flow of the game," he told Fox Sports TV.
"The decision to stay behind for the birth of his child is probably the right one but it will probably cost him a Wallabies jersey for the next few Test matches."
Israel Folau, Karmichael Hunt and Reece Hodge are others who can wear the No.12 with World Cup choice Matt Giteau absent and Kurtley Beale injured.
But Cheika is expected to team up Samu Kerevi with incumbent No.13 Tevita Kuridrani in a big-bodied centre combination that would blunt an anticipated England debut by former NRL star Ben Te'o.
Horan hoped Cheika ignored the likes of Beale, who had talked up Folau's selection in the centres, after his success in the NSW Waratahs' No.13 jersey.
"You could push Kuridrani into 12 and then move Folau to 13 where he has been really impressive for the Waratahs," Horan said.
"But personally, I would much rather see Folau at 15.
"If we are to beat the All Blacks later this year, you need Israel under the high ball at 15."
Another dilemma for Cheika was his two starting locks.
Former Wallabies skipper James Horwill appears to be vying with Brumbies bolter Rory Arnold to partner World Cup squad member Rob Simmons.
England coach Eddie Jones claimed Cheika would never start an uncapped lock but Simmons believed rookie Arnold would excel.
"He's come a long way in 12 months," Simmons said.
"He is fit enough. I think he is definitely up to it."
Greg Holmes might also start as tighthead prop ahead of Sekope Kepu (shoulder).
Possible Wallabies XV: Israel Folau, Dane Haylett-Petty, Tevita Kuridrani, Samu Kerevi, Rob Horne, Bernard Foley, Nick Phipps, David Pocock, Michael Hooper, Scott Fardy, Rob Simmons, Rory Arnold, Greg Holmes, Stephen Moore (capt), Scott Sio.