Christian Lealiifano will be all three for the ACT Brumbies this year and his return to training on Tuesday is a perfectly-timed boost as the team attempts to end a 17-year hoodoo in New Zealand.

Lealiifano was back in the gym doing weights with his Brumbies teammates after going into remission following a 100-day treatment in Melbourne after being diagnosed with leukaemia.

His playing comeback is still at least three months away. But Lealiifano is a Brumbies co-captain alongside Sam Carter and will take on back-line coaching duties.

"We're still paying him so he's got to do some work for us," joked Brumbies coach Stephen Larkham.

"As co-captain he'll still have influence on the players, in the locker room, out on the field and then from a coaching capacity," said Brumbies coach Stephen Larkham.

"We'll certainly use him as one of the coaches in the early stages of his rehabilitation back into playing.

"He was in the gym today, so he started his rehab program to get back to playing but then he's also involved in the units meeting, he was presenting some of the training from yesterday.

"He's down on the field giving advice to the players and he's going to take a pretty big hand in the kicking coaching for the short-term.

"He's got a fairly important role in the group and quite a busy one at the moment."

The Brumbies start their Super Rugby season against the Canterbury Crusaders in Christchurch on Saturday night.

It's a match they would dearly love to have Lealiifano for given they have a woeful record of playing against Super Rugby's most successful club.

The Brumbies have won just two games in Christchurch in Super Rugby history. Their last win was in 2000.

They have lost their past six games against the Crusaders at home or away, and the Crusaders average 40 points in all of those defeats.

Lealiifano's advice at training will be crucial for rookie playmaker Wharenui Hawera and scrumhalf Joe Powell, who will test their combination for the first time in a daunting environment.

Christian Lealiifano and Henry Speight. Photo: rugby.com.au/Stuart Walmsley

Hawera will take Lealiifano's flyhalf job in his first Super Rugby game while Powell will step up for the injured Tomas Cubelli.

Lealiifano will be on modified training duties and juggle his hunger to play again with maintaining his health as he aims to make a comeback.

"The doctor, the specialists have spoken to [Lealiifano] about the six-month mark [after a bone-marrow transplant] as being his target, so we're certainly not going to push anything before that," Larkham said.

"I certainly want to see him back training with us by the end of the season, playing with us, that'd be unbelievable.

Christian Lealiifano has restarted training with the Brumbies on limited duties. Photo: rugby.com.au/Stuart Walmsley

"If he stays in remission for the rest of his life, that's the number one goal for now.

"I know he's got this journey that he's been on and he wants to get back and play rugby at some stage, so I'll help him facilitate that if I can."

Larkham will finalise his team on Thursday before the team travels to Christchurch.

Prop Scott Sio (hamstring) is unlikely to play while Allan Alaalatoa (hamstring) and Jarrad Butler (lower leg) have recovered from injuries to be in selection contention.

If Alaalatoa plays, he will line up against older brother Michael for the second time in their respective careers.