David Pocock's season over after second knee reconstruction in two seasons

Pocock had a knee reconstruction on Wednesday night, almost exactly 12 months on from his initial anterior cruciate ligament injury last year.

It's a heartbreaking blow for Pocock, who has played just five games since the start of 2013, and for the Brumbies as they chase the Super Rugby title.

"Devastated but trying to keep perspective," Pocock said on Twitter on Wednesday night.

"So appreciative of all the support I've received."

Pocock, 25, had an arthroscopy on Wednesday and surgeons decided the damage was so bad it was best to do an immediate reconstruction.

The traditional reconstruction, which grafts hamstring tendons on to the knee, will require another nine-month recovery.

It's a bitter pill to swallow after Pocock made his comeback last month following the same injury on his left knee in March last year.

But Brumbies director of rugby Laurie Fisher is confident Pocock can return in career-best form next year.

Pocock will have just one Super Rugby season to relaunch his career and chase selection for the 2015 World Cup.

"Having worked so hard to get himself back to peak physical condition over the last 12 months it's impossible not to feel for David," Fisher said.

"Only yesterday he was speaking about how much enjoyment he'd been getting out of his rugby this year, so to have him sitting out the rest of our campaign is bitterly disappointing for him and the rest of the team.

"What we must remember is that David is still young and will have more opportunities to play professional rugby in the future. Guys like Ben Mowen and Christian Lealiifano are living proof that you can make a successful comeback from a recurring injury and I'd expect to see David bounce back in the same way.''

Pocock injured his left knee against the Western Force last weekend when it appeared to buckle as he attempted to change directions.

The Brumbies play against the Wellington Hurricanes in New Zealand on Friday night.

The club will wait until after the match before deciding if they need to recruit another player to provide roster depth.

Australian rugby great George Smith looms as one potential candidate.

The Brumbies and Smith have not spoken and Smith has signed a two-year deal with French club Lyon.

Smith will return to Australia next week for a well-earned break after 18 months of consecutive rugby.

Smith's management says it's unlikely the veteran of 142 games for the Brumbies and 111 Tests for the Wallabies will make a Super Rugby comeback this year.

But they stopped short of completely ruling out another Smith cameo appearance.

Pocock has played 46 Tests for the Wallabies and 74 Super Rugby games.

The Brumbies fly to New Zealand on Thursday morning for the clash against the Hurricanes.

Rookie Jarrad Butler will be thrown into the No.7 jersey and faces the daunting task of trying to fill Pocock's shoes.

The Brumbies will shuffle their forward pack - Leon Power will start at lock, Scott Fardy will shift to blindside flanker and Ben Mowen will move to No.8.

Pat McCabe will play at inside centre, despite being taken to hospital in a neck brace less than a week ago.