The powerfully-built back-rower will get another chance to prove himself when the Brumbies host the Queensland Reds in the last game of the regular season this weekend.

Valetini is set to keep his spot in the Brumbies' starting side for what will be just his 11^th Super Rugby game.

The 20-year-old has already been earmarked as a future Wallaby and the Brumbies' play-off charge can boost his hopes of earning a ticket to the World Cup in Japan.

But Valetini thought his Wallabies chance had been crushed when his knee twisted awkwardly three months ago. It was his third knee injury in 13 months and Valetini feared the worst.

"I thought that was it, I thought my season was over," Valetini said.

"I thought I had done my [anterior cruciate ligament] because I'd never felt anything like that before.

"I was really devastated when I walked into the change rooms ... I haven't caught a break yet from injury. But I got good news when I got scans, it was a huge relief and I got confidence from that.

BRUMBIES NEWS

"It was the best rehab I've had so far and I came out in better shape because I got confidence knowing I could get back on the field this year. Now I'll just take it one step at a time and see how I go."

Brumbies coach Dan McKellar will finalise his team on Thursday, with minimal changes expected after winning the past five games.

Winger Henry Speight (foot) is in contention to make his comeback after missing last week, while Scott Sio is expected to start in his 100^th game as part of a rotation with James Slipper.

The Brumbies will be aiming for their seventh win in a row at home after losing just once in Canberra so far this season.

They also have a chance to equal a club record of six consecutive wins. The Brumbies have achieved the winning streak record just once in the past 23 years.

Valentini said the players were riding a wave of confidence, but insisted they wouldn't be lured into complacency in the battle against the Reds.

The Reds haven't won in Canberra since 2014, but they have thumped the Brumbies in Brisbane earlier this season. The Brumbies say the 22-point defeat was the turning point in their season and made the players more accountable for lazy preparation.

"We're all on each other if we muck up ... we're all willing to put in and I can see that we've got something special. But it's all about delivering on the field," Valetini said.

"Just trying to get selection keeps everyone on their toes. We've got plenty of depth in the back row and we're all really close. We all back each other, whoever starts or whoever is on the bench."

The Brumbies will celebrate their inaugural Pasifika Day at the Reds game, with the players to wear a special jersey which represents the Polynesian backgrounds of players.

The Brumbies have organised for Youth in Union to be the game-day charity partner, adding extra motivation for the players given Lachlan McCaffrey is an ambassador for the organisation.

McCaffrey has been working with the Brumbies to collect boots, balls, shorts, jerseys and socks to send to underprivileged players in the Pacific Island nations and went on a trip to Tonga last year.

SUPER RUGBY ROUND 18

Saturday: ACT Brumbies v Queensland Reds at Canberra Stadium. Tickets available from Ticketek.