The former ACT Brumbies playmaker is back in Australia and has spoken with Wallabies coach Michael Cheika about potentially playing in the first Test of the Rugby Championship in Sydney on August 18.

Toomua is expected to sign a two-and-a-half year contract with the Rebels to reignite his Australian rugby career and his hopes of playing at the World Cup next year.

He will play in England for Leicester this season. But the benefit of his future move to the Rebels is that it makes him immediately available for Wallabies duties if required.

The Wallabies' outside centre injury woes with Tevita Kuridrani and Samu Kerevi has forced the Wallabies into a back-line rethink. That could open the door for Toomua's return.

It's understood Toomua is a real chance to play for the Wallabies against the All Blacks, marking what would be a unusual return to Australia given he still has playing commitments abroad.

At this stage it appears Toomua is committed to the coming season at Welford Road and will not link up with the Rebels until the latter part of 2019 or the start of 2020.

The Brumbies were keen to lure Toomua back to Canberra to partner with Christian Lealiifano again, but the 33-Test Wallaby decided on a move to Melbourne for family reasons.

His return is a massive boost for the Wallabies flyhalf stocks. Test coach Michael Cheika has been relying on NSW Waratahs pivot Bernard Foley for the past two years with no full-time flyhalf option as a back up.

Quade Cooper is eligible to play for the Wallabies, but he has been shunned by the Queensland Reds and is playing in the Brisbane club rugby competition.

Kurtley Beale and Reece Hodge have been Foley's back ups, while Jack Maddocks could emerge as a future option and Australian under-20s star Hamish Stewart has also been added to the extended Test squad.

Cheika will trim his extended squad when the Waratahs finish their Super Rugby season. The first Test against New Zealand is on August 18, giving the bulk of the Wallabies almost one month to prepare.