White will step up as a 22-year-old skipper to lead the Brumbies in the absence of regular captain Ben Mowen in the clash with the Melbourne Rebels at Canberra Stadium.

It is a massive challenge, with a host of senior Brumbies players missing and the team on the cusp of breaking an eight-season finals drought. It's also a boost for White after the highly rated scrum-half was left out of the initial Wallabies squad for the British and Irish Lions series.

Gregan - the most capped Brumbies captain and a former Wallabies skipper - rates White as the second best No.9 in Australia behind Will Genia but urged him to find the right balance between passion, aggression and leadership when he takes charge.

''He's going to respond to the captaincy really well, but there's a balancing act. You can't lose too much [of the fire] because that's what makes him the type of player he is,'' Gregan said.

''It's a balance between not going too far in being too fiery or too temperamental, as well as avoiding going too far the other way, where he wouldn't be himself. That's the most challenging aspect for him, but he's definitely up for it.''

The Brumbies can all but secure a play-off spot if they beat the Rebels with a bonus point.

Mowen is in camp with the Wallabies as they begin preparations for the Lions series.

The Brumbies are also missing senior stars and captaincy candidates in David Pocock, George Smith, Stephen Moore, Christian Lealiifano and Ben Alexander through injuries and Wallabies duties.

White was in camp with the Wallabies on Tuesday and is still in contention to claim one of the remaining six places available for the Lions series.

And in a week full of distractions, the advice from Mowen was simple: don't become ''White noise''.

''This is something I'm pretty proud of, I'm on cloud nine a little bit,'' White said.

''This is a huge honour and something I'm not taking lightly. [Mowen] just said don't become White noise, don't talk too much. You don't want to become background noise, it's about picking your times and picking your points.''

A rollercoaster ride since the end of last year has helped White mature. He was on the Wallabies bench before deciding to have a shoulder reconstruction instead of playing at ''70 per cent''.

A week later Genia ruptured his anterior cruciate ligament and White missed his chance to be Australia's starting No.9.

He nursed a busted shoulder through the off-season and a broken jaw after he was king hit at a music festival last November.

But Jake White said the ride had given the player the steely edge to be a perfect leader. ''He's matured a massive amount,'' he said.

''You can't get any closer to a Wallabies spot than sitting on the bench and not playing … he's had to go through a lot and the way he's handled it … is a sign of maturity.''