Stephen Larkham backs ACT Brumbies' Ryan Lonergan for Rugby World Cup role if Wallabies face Tate McDermott dilemma

There's some uncertainty facing the Wallabies squad in France with vice-captain Tate McDermott stood down for 12 days as per protocols due to a nasty concussion suffered in the Wallabies' World Cup win over Georgia.

It rules McDermott out of the Wallabies' match in Saint-Etienne against Fiji next Monday - at least - with Nic White and Issak Fines-Leleiwasa the only other halfbacks in the squad.

Fines-Leleiwasa made his Test debut in the World Cup warm-up match against France off the bench.

The situation now leaves the Wallabies vulnerable at the position which could open the door for a shock call-up for Lonergan, who is currently in the United Kingdom with the Barbarians.

Larkham said if concussion issues linger for McDermott, Jones should have no hesitation calling up the Brumbies No.9.

"He's been training in the squad all the way up until the final World Cup selection, so if a halfback were to be ruled out for a significant amount of time, then Ryan has to be top of the list," Larkham told The Canberra Times.

"You'd have to assess Tate and see how his recovery was going, because with HIAs you have to take it seriously.

"It is a 12-day return-to-play now, but it used to be seven days. I'm assuming he's only missing one game, and you'd keep someone in the squad if that's the case.

"But from my perspective, it's a no-brainer that Ryan would be tremendous for the squad."

Any replacement in the World Cup squad would be a permanent one, with the newly-added player eligible to compete 48 hours after they join.

Lonergan has had experience in the Wallabies squad, and Larkham said the Barbarians tour has kept him in peak condition to step up if needed.

The coach said even the Brumbies that missed out on World Cup selection "haven't had a break" as they prepare for a two games in Japan from October 1, meaning they too are ready.

"Ryan played in the Barbarians game last week against Northampton and was outstanding. I thought he was worthy of player of the match," Larkham said.

"Part of the reason having our players picked in the Barbarians in Europe is to allow them to be on call for the Wallabies. They're playing and training regularly so they're certainly ready to go.

"They're all ready, those that were in the squad this year who weren't picked. Their mindset is to stay fit."

White played through a minor shoulder complaint against Georgia, while Wallabies veteran James Slipper and Pone Fa'amausili are on track to return from injury against Fiji.

Australia v Fiji at Saint-Etienne in France, Monday 1.45am

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