Conor McKenna's "phenomenal" return to the AFL this season has far exceeded Brisbane's expectations for the dashing defender, says the club's football manager Danny Daly.

After finishing up with Essendon at the end of 2020, McKenna went back to Ireland to play two seasons of Gaelic football with Tyrone before returning to the AFL.

On Saturday against Adelaide, the 27-year-old will play his 100th career game, 20 of which have come this season without a miss.

Although McKenna said he was "bullish" about making an immediate impact, Daly said the club was prepared for a slower return to his best.

"To be perfectly honest we thought it'd take him eight or nine games to get back into the flow of things and he'd be really important for us in the back half of the year," Daly said.

"That's how we looked at it.

"For him to play every game so far is a lot more than what we expected.

"Two years away playing a different sport and being able to come back and do what he's been able to do is pretty phenomenal when you think about it."

McKenna had interest from Geelong, Port Adelaide and Essendon, but opted for the Lions as he sought to add to his two finals appearances with the Bombers.

His impact has come both offensively with his daring run and carry, but also defensively, with his combativeness and speed to close down opposition space.

Brisbane took his pre-season cautiously. Daly said McKenna was treated like a first-year player as he was re-integrated through December and January, to minimise the risk of injury.

However, he progressed quickly and forced his way into the top-four team during practice matches.

The transition came through hard work.

"I was pretty bullish," McKenna said.

"I wanted to play as many games as possible. My first goal was to play round one, get in the team, tick that off the list and then build consistent football.

"When I first went home, I didn't do any gym work for two years. I'm not a massive fan of gym, so I had a break.

"I probably lost three or four kilos of muscle mass, so that was probably the main thing coming back here, getting back in the gym on a daily basis.

"I actually struggled (with the running) going back home to play Gaelic. You don't really get a break in Gaelic. It goes for 70 minutes and normally you don't come off.

"AFL at least you get a break once a quarter, which is pretty good."

Daly said not only had McKenna fitted in on the field, but off it as well, with his jovial nature a nice complement to quieter backline teammates like Brandon Starcevich, Jack Payne and Keidean Coleman.

He also has a passion away from the football field – horses.

McKenna heads to Eagle Farm or Doomben Racecourse regularly for trackwork at Rob Heathcote's stables.

It's just a small part of the reason he has adapted to life in his new city so quickly.

"He's been a great pick-up for us," Daly said.

"He's certainly gone well beyond what we thought he'd be able to output this year and he's going to be pretty important to us for the last few weeks and finals."