A double dose of Irish pace will power Brisbane's premiership push, Darragh Joyce and Conor McKenna holding high AFL hopes after finding new homes at the Lions.

The defenders will join countryman James Madden at the Gabba this season, their speed and skill in the backline a tasty proposition for a side already boasting a stacked midfield and forward line.

Joyce, signed as a replacement for the inactive Marcus Adams (concussion), grew up at the opposite end of Ireland to northerner McKenna.

But the pair befriended each other in 2016 when playing for St Kilda and Essendon respectively and are now housemates in Brisbane and want to win a flag.

"I never thought we'd be at the same club," Joyce told reporters after training on Wednesday.

"I'm not as fast as this man (McKenna) but ... hopefully I can show it up and use my speed going into offence."

Joyce comes to Brisbane after six years with the Saints that delivered 13 AFL games, three of those last year.

At worst he'll provide good depth and more selection options for last year's preliminary finalists.

"Brisbane had been keeping tabs on me the last couple of seasons, behind the scenes, when the call came I jumped," he said.

McKenna was one of the Bombers' key men before he headed home for two years, dominating the Gaelic competition to lead Tyrone to an All-Ireland victory.

He said after about six months he "got the itch" to return to Australia and, chased by four clubs, described Brisbane as the clear choice.

"They were probably the club closest to winning the premiership," he assessed.

"I want to be competing deep in the finals."