Toomua has been called into the starting side to play a third Test dead-rubber against England in Sydney on Saturday night, leapfrogging Brumbies teammate Christian Lealiifano to snatch the inside centre spot.

The match doubles as Toomua's comeback from knee surgery that threatened to prematurely end his time in Australian rugby.

Toomua has signed a deal with English club Leicester for the next three years and he doesn't meet the ARU's 60-Test threshold to be eligible for international duty while playing abroad.

But the 26-year-old said he wanted to play for Australia as much as possible this year, including the Rugby Championship and Bledisloe Cup, before linking with Leicester.

"If I get picked [for the rest of this year] then I'll be available to play. In my mind I'm here until I'm needed ... I'd never turn my nose up at a Wallabies jersey," Toomua said.

"This is definitely my priority at the moment and I do know there are a finite number of Tests left for me in the near future at least.

"There's no shortage of motivation for me. Every game is an audition and I see an opening and opportunity to have my name read out as the No.12 for a while now.

"I want that so I'll do everything I can to get it. I know I'm going at the end of the year and for a while I didn't think it would happen again with my injury."

Toomua's return will be a welcome boost for the Brumbies ahead of their pursuit of a Super Rugby finals berth.

Toomua hasn't played since the Brumbies lost to the Highlanders in Invercargill at the end of April, but is set to return to the starting XV against the Queensland Reds after the final Test against England.

His inclusion in the Wallabies comes after they failed to land any attacking blows last weekend as England defended their way to a historic series victory.

Australian coach Michael Cheika has ditched plans to run giant centres Samu Kerevi and Tevita Kuridrani together to ease the pressure on Bernard Foley as the hosts attempt to salvage some pride against their English enemies.

"I do see [helping Foley] as something I have to do, share those playmaking responsibilities," Toomua said.

"The guys who have been out there have been good, but myself, coming in probably changes the dynamic a little bit.

"We are a proud team and we have been dented a bit in the last few weeks. There's a lot to play for. We definitely want to restore some pride."

Toomua's inclusion in the starting side came at the expense of close friend Lealiifano, who is set to keep his place on the bench for another Test.

Most expected Lealiifano to get a chance in the starting XV ahead of Toomua, given the latter hasn't played for two months.

But the roles are reversed before they team up in Canberra next week to guide the Brumbies through a tough run to a potential Super Rugby finals spot.

The Brumbies play the Reds, the Auckland Blues and the Western Force in their last three games of the regular season and are one point behind the NSW Waratahs on the Australian ladder.

"The games just get bigger and bigger from now on, and I know I've only got limited time left so I'll be making sure I don't leave anything out there," Toomua said.

"Christian and I are very close and it's hard to compete with one of your best mates, I won't lie.

"But we sit next to each other on the bus ... it ebbs and flows, we've swapped and changed over the last eight years so I've got to take my chance."

Meanwhile, the Brumbies are in contention to lure Western Force back-line star Kyle Godwin to Canberra next season and Perth-based teammate Chris Alcock could follow.

Godwin would be readymade replacement for Toomua and would get the chance to work with Larkham while Alcock could slot into the openside flanker position temporarily vacated next year when David Pocock takes a sabbatical.

Wallabies squad to play England in third Test

1. James Slipper - Reds (76 Tests)

2. Stephen Moore (c) - Brumbies (104 Tests)

3. Sekope Kepu - Waratahs (65 Tests)

4. Will Skelton - Waratahs (14 Tests)

5. Rob Simmons - Reds (61 Tests)

6. Scott Fardy - Brumbies (32 Tests)

7. Michael Hooper (vc) - Waratahs (53 Tests)

8. Sean McMahon - Rebels (8 Tests)

9. Nick Phipps - Waratahs (41 Tests)

10. Bernard Foley - Waratahs (29 Tests)

11. Rob Horne (vc) - Waratahs (31 Tests)

12. Matt Toomua - Brumbies (31 Tests)

13. Tevita Kuridrani - Brumbies (33 Tests)

14. Dane Haylett-Petty - Western Force (2 Tests)

15. Israel Folau - Waratahs (40 Tests)

Reserves (one to be omitted)

Tatafu Polota-Nau - Waratahs (63 Tests)

Scott Sio - Brumbies (17 Tests)

Greg Holmes - Reds (25 Tests)

Adam Coleman (Uncapped)

Dean Mumm - Waratahs (46 Tests)

Wycliff Palu - Waratahs (57 Tests)

Nick Frisby - Reds (2 Tests)

Christian Lealiifano - Brumbies (17 Tests)

Taqele Naiyaravoro - Waratahs (1 Test)