McCabe feared he would never play rugby again when he broke his neck in the Wallabies' series against the British and Irish Lions last year.

But as McCabe prepares for his 50th Super Rugby game, the man known as ''Knick Knack'' is determined to bury an injury-cursed 15 months, which has limited him to just seven games since November 2012.

McCabe admits he almost quit rugby when he broke his neck on the Wallabies' spring tour in 2012 and fractured the same C1 vertebra again against the Lions.

Throw in almost six months in a neck brace, a torn hamstring, knee ligament damage and another head knock two weeks ago and the easy option would have been to walk away.

''But I wasn't happy with what I achieved and the performances I put out there for the Brumbies and the Wallabies. I felt like I hadn't achieved everything I wanted to,'' McCabe said.

''There were certainly times I thought I'd never play again … I definitely wanted to play, but didn't know if I would.

''But there was a belief that I could be better and now I want to show that … that's kept me going.''

McCabe will form a surprise centres combination with Andrew Smith in the Brumbies' season opener against the Queensland Reds at Canberra Stadium on Saturday.

McCabe and Smith are the only two players in the Brumbies' back line who didn't feature in last season's Super Rugby grand final.

They are also keeping Wallabies outside-centre Tevita Kuridrani on the bench as he makes his comeback from a five-match International Rugby Board suspension for a lifting tackle.

McCabe has a chance to cement his place back in the starting XV with Wallabies No.12 Christian Lealiifano out of action with an ankle injury for the first five rounds.

''We think Pat has earned the spot and he's ready to go,'' Brumbies director of rugby Laurie Fisher said.

''He was fantastically robust. I see a bloke ready to go and ready to show what he's capable of doing.

''Tevita had a wonderful season last year, but he has to earn his spot again.''

The Brumbies will also inject former Reds back-rower Jarrad Butler for his first game for the club. Superstar flanker David Pocock will play just his fourth game for the Brumbies in his return from a knee reconstruction.

Pocock arrived in Canberra last year as the Brumbies' marquee recruit, but tore his anterior cruciate ligament in his third game for the club.

McCabe, who has played 20 Tests for Australia, hasn't spoken with new Wallabies coach Ewen McKenzie and has put his international ambitions on the backburner until he revives his Brumbies career.

McCabe's comebacks have been halted by injuries.

Twice a week he uses a helmet with metal chains connected to a wall to strengthen his neck.

But he insists confidence and nerves won't be a factor as he runs out for his milestone match.

''I'm not even thinking about Wallabies … if we can perform well at the Brumbies, I believe more than ever the other stuff looks after itself,'' McCabe said.

''Some people will think I'm crazy for coming back. [The injuries] give you perspective about where rugby fits in your life and some people will doubt that now that I'm coming back.

''But rugby is a small part … while I can still do it I want to play. You get more confidence with the knocks you cop.

''The past 10 or 15 games have been tough to get. But I'm proud to get to 50 games for the club I love.''