Wallaby debutant Richard Brown has been admonished for man-handling quokkas but has a licence to rough up All Black captain Richie McCaw in Saturday night's Tri Nations decider.

The Western Force flanker looms as a shock weapon off the bench to combat Kiwi superman McCaw, who has the potential to terrorise Australia in the so-called "Battle of Brisbane" at Suncorp Stadium.

It is the most daunting of tasks for 24-year-old Nudgee College old boy Brown, who grew up on a cattle station in the remote Queensland town of Julia Creek, especially given he lists McCaw as his sporting hero on the Force website.

Australia has stacked the bench with five forwards for the epic Bledisloe clash, possibly in a bid to at least temper the impact of the ubiquitous All Black open-side flanker, who was this week described as "colossal" by his coach Graham Henry.

For his part, McCaw admitted the make-up of the Wallaby interchange could be intended to curtail his perpetual pestering at the breakdown, which has turned Bledisloe matches before and could do so again given his form is bordering on career best.

"Could well be. That may be a plan. I'm not sure," McCaw said. "Certainly fresh legs coming on, when they need an injection of that they'll be hoping it brings something late in the game. I guess we'll see.

"Perhaps it indicates they want to keep the pace of the game up, I don't know. It might be out of necessity. I really don't know. I don't think it will change how they play too much."

The Wallabies tried to double-team McCaw when George Smith and Phil Waugh paired up in the second Bledisloe clash in Auckland, although the result was a compromised line-out and a 39-10 belting.

Trying to engineer a way to stop McCaw is a bit like trying to unravel the meaning of life. Everyone has had an opinion but a definitive answer remains as evasive as the Higgs Boson.

Wallaby assistant Jim Williams said Brown was itching to prove himself against the very best and in a case of "be careful what you wish for", will be given that chance on Saturday.

"You're playing against the best and you want to be the best yourself. Playing against guys like Richie does inspire guys," Williams said.

"Certainly with our backrowers, guys like Richard Brown are dying to get on there and have a crack at Richie as well, and see how good he is himself. He (McCaw) certainly raises the level of opposition teams, opposition forwards and certainly opposition backrowers."

If Brown can play a pivotal role in a Tri Nations and Bledisloe victory, it will complete a remarkable rise to redemption after a controversial incident in December of 2007, where he was fined for anti-social behaviour and running nude among the quokkas on Rottnest Island.

Brown has elected to avoid the media this week, preferring to deflect any additional pressure in his first Wallaby outing. Williams, meanwhile, has been busy devising strategies that may lessen McCaw's influence on the outcome.

"Trying to isolate him and target him as individual makes it very difficult. His great attributes are his speed to the breakdown, his ability go get there first," Williams said.

"It's all about trying to get him out of position I think. If we can get over the gain line early, he's chasing the ball a little bit and then we've got two or three numbers there and then we're shifting the ball away. That's probably our best bet."

McCaw is less concerned with rookie Brown and more worried about the returning Rocky Elsom, who missed the Wallaby loss in Auckland.

Elsom's abrasive play, line out abilities and strong running may be just what the Wallabies need to reclaim the Bledisloe for the first time since 2003.

"I think they did miss Rocky Elsom in that Test in Auckland, obviously at the line-out but he's a pretty good ball carrier as well. I think they get quite a bit from him," McCaw said.

"It will add a bit, with the line-out it will help and just with his energy to the team."