But Lealiifano is inspired by the people he met, the leukaemia patients who touched his heart and the hope his story can help others through the tough times.

The ACT Brumbies co-captain will make his full-time Super Rugby comeback this year, starting with a clash against the Japan Sunwolves in Tokyo on Saturday.

It will be his 11th Super Rugby season, but this one is different because of who Lealiifano has become and the people he connected with on his road to recovery.

People like Mick Callanan, a stranger who walked into Lealiifano's hospital room and opened up about his 12-year fight with cancer.

It was the start of a friendship that led to Callanan sitting in the stands to watch Lealiifano make his Super Rugby comeback in a quarter-final last season.

"Unfortunately Mick has passed, but I'm glad he doesn't have to go through the pain any more," Lealiifano said.

"To lose someone you've got to know on this journey is hard ... heartbreaking.

"When I reflect about Mick and AJ [Frijo] ... AJ is doing it tough. He's in and out of hospital on his journey.

"That saddens me a bit when I'm at the gym or running around playing competitive sport or being with my family.

"But it definitely inspires me that they have drive and they push for a positive outcome. It also makes me grateful.

"Not everyone has the outcome I've had and that's tough. This season is different because of the person I am right now and what I've been through.

"It's not just a normal game any more. It's an absolute bonus and a blessing to be playing footy again."

Lealiifano is set to reclaim the familiar No.10 jersey for the Brumbies' season opener.

The fact he will do so in Japan and the Brumbies will use the Suntory Sungoliath facilities this week will be somewhat of a strange twist to his story.

Lealiifano had signed a deal to join Suntory at the end of 2016 and was getting ready to fly to Tokyo when a fitness session at Brumbies headquarters changed his life.

The 30-year-old was feeling unwell, and seeing hooker Robbie Abel blast past him in a running session convinced him to see the Brumbies doctor.

Since then he has had chemotherapy, a bone-marrow transplant, went into remission, became a Brumbies waterboy and eased his way back onto the field in June last year.

"The moment of the comeback has already past. I don't think there was one moment, for me it's just about enjoying each day," Lealiifano said.

"I've got a much bigger appreciation [for rugby]. Everyone talks about putting the jersey on ... to actually have an opportunity to put it on again is really, really different now and that excites me."

The veteran playmaker will be part of a double Brumbies comeback alongside David Pocock this year. It's hoped the return of the duo will give the Brumbies the extra edge they need to win a Super Rugby title.

Pocock and Lealiifano have known each other since they were teenagers, teaming up in the Australian junior sides before joining forces at the Brumbies.

"To see someone facing adversity that I've never known and to see how positive Christian was, he's a really special guy," Pocock said. "People speak highly of him and rightly so."

Pocock is returning from a different sort of break from Brumbies duties, taking a 12-month sabbatical from Australian rugby to do conservation work in Africa and play in Japan.

"There is a lot of unknown this year. In Canberra you've got Poey and Christian coming back and that's why this year is going to be hard to separate," said Wallabies captain Michael Hooper.

"Christian's always in a good mood - the teeth are back. He's always smiling and I'm such a big fan of his.

"The positivity that someone like Christian brings to a squad, that's a massive commodity for any team. It's not only great for the Brumbies, but Australian rugby."

SUPER RUGBY ROUND ONE

Saturday: Japan Sunwolves v ACT Brumbies at Prince Chichibu Memorial Stadium, Tokyo, 3.15pm. TV time: Live on Fox Sports.