Tim Horan rates Michael Hooper a 50-50 chance of World Cup selection and hopes Rugby Australia "give him the option" to go out on his terms if the Wallabies champion isn't on the plane to France.
Eddie Jones will confirm his 33-man squad for next month's showpiece on Thursday, Hooper's status looming as the biggest call.
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The returning coach's first move was to name Hooper as co-captain alongside James Slipper.
But the 31-year-old was ineffective in a heavy loss to South Africa and is battling a calf injury that's kept him out of the side's last three Tests.
In that time Tom Hooper and Fraser McReight have shown their wares in the No.6 and 7.
Jed Holloway and Rob Leota have been employed as cover in the lock and No.6 positions, while versatile back-rower Pete Samu could still earn a spot despite being cut for the Bledisloe Cup.
Jones could also opt to take another prop as cover, given Taniela Tupou is nursing a rib injury after a long rehabilitation from a torn Achilles.
It leaves the 125-Test veteran, who is yet to confirm his playing future beyond this year, in a fight to feature at a third World Cup.
"It's probably a 50-50 call," two-time World Cup-winning Wallabies centre Horan told AAP.
"For what he's done for the game and Wallabies brand in a difficult period over the last 10 years, plus his current leadership and ability, I'd be picking him.
"But he's probably the No.2 or No.3 in line, fourth if they do go with Samu, who would be one of my first forwards picked.
"So if he doesn't go, I hope Rugby Australia give him the option (to announce his Test retirement)."
Jones turned to youth with relative success in last Saturday's All Blacks Test, a halves pairing of debutant captain Tate McDermott and Carter Gordon giving the Wallabies an early 17-3 lead before they were pipped 23-20.
That performance meant the 23 players used in Dunedin have likely punched their tickets, Samu Kerevi and David Porecki picking up injuries that shouldn't jeopardise their French campaigns.
Hooker Jordan Uelese and outside centre Len Ikitau are likely inclusions too as they recover from injury.
The assured Andrew Kellaway replaced the axed Tom Wright at fullback for the Bledisloe Cup while Jordan Petaia wore the No.13, but could fill any spot in the backline.
Ben Donaldson and Dylan Pietsch haven't played a minute under Jones but been retained in his squads as utilities, rated as precious in a Cup campaign, while veteran Bernard Foley is likely relying on the coach picking a third five-eighth if he's to join Carter and Quade Cooper in France.
The squad will gather in Darwin for a four-day camp from Thursday before an official farewell in Sydney next week.
The Wallabies, who have sunk to No.8 in the world, will play the host nation in a final World Cup tune-up on August 28 (AEST) before their opener against Georgia on September 10.
