The 26-year-old has been one of the most scrutinised players in Australian rugby in recent years, a number of brain fades seeing him receive multiple cards at Super Rugby and Test level.

Swain was sent off for a head butt against England in 2022 and received a six-week ban for an awkward clean out of All Blacks forward Quinn Tupaea later in the year.

The incident threatened to set off a bitter trans-Tasman feud, with a number of former New Zealand players criticising Swain.

Retired All Black Israel Dagg labelled the Wallaby a "thug", while coach Ian Foster called for a long suspension. Eighteen months on, the Waikato Chiefs are still seething about the incident.

Former Wallabies coach Eddie Jones told Swain his ill-discipline cost him a place in the World Cup squad last year.

The lock, however, was instantly remorseful after the Tupaea incident and has worked hard to eliminate penalties from his game. Despite his reputation, he has conceded just one penalty this season and has emerged as a leader within the Brumbies pack.

Swain put the disappointment of the Wallabies omission aside to captain ACT during a tour of Japan and impressed players and staff with his leadership of the team.

While the decision to name Swain captain for Friday's game against Moana Pasifika shocked many, Brumbies coach Stephen Larkham said it was an easy decision.

"It's apparent in the environment and working with him that he stands out as a strong leader," Larkham said.

"He's fairly experienced, he speaks well in group situations and he was captain for us in Japan for two games. He did a good job over there, he leads both by example and through his communication.

"We've got some experienced players on the bench, we think Darcy is the right guy to start the game."

The Brumbies will host a double-header at Canberra Stadium on Friday, with the Super W side to play the Melbourne Rebels in a crucial clash at 5.05pm. The men will then take the field in the second game of Kids Round.

Swain's captaincy comes as clouds swirl over his future with the club. The Western Force have launched an audacious bid to lure the Wallabies lock to Perth and while ACT officials are eager to retain the star, they privately concede he may depart at the end of the season.

The forward has worked hard to change the public perception and completes plenty of community work away from the spotlight.

On the field, Swain walks a fine line of controlled aggression and acknowledges he has in the past inadvertently crossed it.

Larkham recognises it's a hard balance to navigate but praised the lock for working on his accuracy.

"Darcy plays with an edge, that's what you need from your forwards," he said. "We've worked hard at trying to get his accuracy right. He's not going out there to create a yellow or red card scenario but sometimes his accuracy is a little bit off.

"We've worked hard on trying to improve his accuracy around the contact area, particularly in defence and at the breakdown."