But former Wallabies coach John Connolly and retired Test back-rower Toutai Kefu believe NSW Waratahs star Michael Hooper has already usurped Pocock as Australia's best No.7.

Pocock's season-ending knee injury ruined a highly anticipated openside flanker clash against Hooper when the Brumbies play the Waratahs at Canberra Stadium on Saturday night.

Pocock's absence leaves a gaping hole in the Brumbies' line-up and without a specialist openside flanker.

Smith, 33, has already said no to a potential Super Rugby comeback to answer an SOS from the Brumbies.

But the Brumbies and Wallabies legend said Pocock's injury would not dampen the ACT's championship dreams.

"I think a lot of people do underestimate the Brumbies' forward pack," Smith said.

"But it's hard to underestimate a team that played in the final last season and is only missing a couple of players from that team.

"I can see how an outsider would think the Brumbies' season would be dramatically affected with David out ... but I wouldn't bet against the Brumbies.

"Especially in the game against the Waratahs ... I've never been in a Brumbies team which has needed extra motivation or revved up. It's such an important game and there's personal pride as well."

Pocock had a knee reconstruction last week for the second time in 12 months.

With Pocock limited to just five Super Rugby games since the start of last year, Hooper has stamped himself as the Wallabies' first-choice ball fetcher.

Pocock is regarded as one of the world's best flankers when he is fit.

But former Wallabies mentor Connolly said Hooper was ahead in the No.7 race.

"I think potentially he's [Hooper] the best openside flanker in Australia," Connolly said. "I think he's a better player than [David] Pocock, he's got a great all-around game."

Former powerhouse Australian No.8 Kefu agreed, likening Hooper to Smith.

"Michael Hooper, he's taken it to a new level," Kefu said. "I even think he's better than [David] Pocock.

"They're both very similar over the ball and their strength around the ruck. But Hooper runs the ball, he's like George Smith."

Smith has been working with the Brumbies this week to launch a mobile phone app during their arch rival clash against the Waratahs.

Smith is one of the founders, along with All Black Ma'a Nonu, of the Waterboy app, which will be used by the Brumbies to broadcast live scores across different social media platforms

The Otago Highlanders have already jumped on board and Smith is keen for the Brumbies to use it for every Super Rugby game.

"It gives you a different angle and commentary than normal," Smith said. "The info comes from within the Brumbies and, with them jumping on board, the users can get a personal touch at the game."

Smith made his Super Rugby comeback in the corresponding Brumbies-Waratahs contest last year.

He expects Hooper to continue his stellar rise to be one of the world's premier openside flankers.

"But the Brumbies won't give him time to set himself in the breakdown area this week," Smith said.

"On paper, it's straightforward and you expect a No.7 to pilfer as many balls as he can. I hope Hooper does play well and make a nuisance of himself."