Brumbies captain Christian Lealiifano

Lealiifano comes off-contract at the end of the season and opted, after 12 season in Canberra, to head overseas.

It's not the first overseas stint Lealiifano has had - he has previously played for Suntory in the Japanese Top League and featured for Irish side Ulster at the beginning of the 2018 season as he worked to get more game time in his recovery from Leukaemia.

The 29-year-old Wallabies utility recently passed 100 days since having a successful bone marrow transplant to treat leukaemia.

His Brumbies outfit has embraced his recovery and he is in their mix for the start of Super Rugby, initially acting as a mentor and kicking coach.

"We'll certainly use him as one of the coaches in the early stages of his rehabilitation back into playing," Brumbies coach Stephen Larkham said in an AAP report.

"He's going to take a pretty big hand in the kicking coaching for the short- term.

Lealiifano told ABC Canberra on Friday that his younger sister had been identified as a bone marrow match, with the transplant likely to occur later this month.

He has been through two bouts of chemotherapy and is currently in remission, but the transplant is the next part of the recovery process.

I've had two treatments of chemotherapy which have pretty much put me in remission going into this transplant so hopefully the transplant goes well and gives me every chance of beating this leukaemia,” he told the ABC.