Lealiifano made a remarkable return from leukaemia in the Brumbies final game last season and then continued his incredible comeback joining Ulster on a five-month loan.

The 30-year-old has been an influential figure at the Irish powerhouse, making 15 appearances and scoring 47 points, despite arriving just a week before the start of the season.

Lealiifano kicked a match-winning sideline conversion against Benetton and was named man of the match in Ulster's massive win against Harlequins on December 16.

His final game will be against Wasps next week, before rejoining the Brumbies with five weeks to prepare for their Super Rugby opener against the Sunwolves on February 24.

ACT Brumbies coach Dan McKellar has kept a close eye on Lealiifano's progress and said he was not surprised to see the playmaker dominating.

"Christian has been playing well, we've spoken quite a bit and he's enjoying it and we've all benefited to this point but he's keen to get home and get stuck into what we're doing," McKellar said.

"Early on it was probably challenging for him from a condition point of view, which was to be expected, but he's certainly been a key player for them with the direction he provides around the park.

"The benefit for Christian was to get away from Canberra, he's played all his rugby at the Brumbies and was due to go and play for Suntory [in Japan] before he was diagnosed.

"He missed that opportunity so it was good he could get away and experience a new life and culture and club and enjoy the time with his family."

Lealiifano will be given a few days to get over his jetlag but after that McKellar said he'll be throwing the veteran into the thick of things to get him up to Super Rugby speed.

"Whilst he's been playing games, I think because of the style of rugby and positional play it's not at the same speed, it's certainly a physical game, but probably not as quick," McKellar said.

"There'll be an adjustment there and we'll make sure we manage his load while getting him through the work he needs to do to get him up to speed with how we want to play."

The prodigal son David Pocock is set to return for the Brumbies next week. Photo: Rohan Thomson

Lealiifano's presence at Ulster has been so popular that he's spent time captaining the side during their Pro 14 and European Champions Cup campaigns.

The Brumbies are yet to name their skipper for next season but McKellar confirmed Lealiifano was amongst the players he was considering.

"Christian has clearly had an impact over there, for a bloke on loan and a foreign player to be made captain goes to show the significant contribution he has made," McKellar said.

"He's in the mix with guys like Sam Carter, David Pocock and others and we'll make an announcement over the next few weeks but regardless of who is captain, those players will all be leaders."

Pocock is also due back in the capital next week after his sabbatical and stint with the Wild Knights finished with a loss against Suntory in Japan's club rugby championship final on Saturday.

"The group has been working hard for the past least six weeks and we're certainly in a good place but being able to add two experienced players of their quality is only going to be a positive for us," McKellar said.

"Right now it's head down arse up, we've been training at a really high intensity since before Christmas and we'll continue that through to the trials and then make sure we're ready to go on February 24."