Brumbies coach Dan McKellar has backed "118kgs of granite" to break a 12-year club hoodoo when they face the Waratahs on Saturday.
The Brumbies are aiming for five straight Super Rugby wins for the first time since Stephen Larkham and George Gregan were running around at the famous club in 2007.
McKellar has changed his back-row for the first time in five games after selecting rising star Rob Valetini to replace Jahrome Brown at blindside flanker.
It marks Valetini's first start in 12 weeks, the 20-year-old having injured his knee during the Brumbies' victory against the Waratahs in round four.
McKellar knows the young gun is a Wallaby-in-waiting, but said his focus for now was getting some minutes into his legs.
"He's excited big Robbie. I just want him to string some games together and play really well for the Brumbies and establish his Super rugby career," McKellar said.
"Rob is going to play for Australia, there's no doubting that but let's just let him get back on the park first.
"We've built his minutes up over a couple of weeks, given him some confidence and I wanted to expose him when the time is right and I feel the time is right.
"I look forward to seeing him on both sides of the ball because he's certainly someone who has that physical presence and can change the course of a game.
"He's 117-118kgs of granite coming at you, I'm sure (Waratahs five-eighth) Bernard (Foley) is looking forward to that."
Winger Henry Speight is out with a leg injury but McKellar expects the Fijian flyer to only miss one week and has replaced him with Andy Muirhead.
The Brumbies are leading the Australian conference after winning six of their past seven games, and can all but secure a home quarterfinal by ending NSW's season at Bankwest Stadium.
But McKellar insisted he wasn't looking at the ladder or records.
"We don't think too much about those stats (five straight wins) but it is good and just says more about how far the group has come from over the last 12-18 months," McKellar said.
"Little milestones like that are good to know and you take them on board, but at the end of the day, they don't mean a lot on Saturday."
Brumbies: James Slipper, Folau Faingaa, Allan Alaalatoa, Rory Arnold, Sam Carter, Rob Valetini, Tom Cusack, Pete Samu, Joe Powell, Christian Lealiifano, Andy Muirhead, Irae Simone, Tevita Kuridrani, Toni Pulu, Tom Banks. Res: Connal McInerney, Scott Sio, Les Makin, Darcy Swain, Lachlan McCaffrey, Jahrome Brown, Matt Lucas, Tom Wright.
