The 27-year-old is locked in fierce competition with former Australian teammate James Slipper for the Brumbies' No.1 jersey.

Brumbies coach Dan McKellar chose former Queensland Reds skipper Slipper as starting loosehead prop for the season-opener against the Melbourne Rebels last Friday night.

Slipper, 29, has earned a rugby lifeline at the ACT franchise after his final season with the Reds in 2018 was ruined by injury, depression and testing positive for cocaine.

He impressed in 50 minutes of game-time against the Rebels, before Sio came on for the final half-an-hour.

Sio says having Slipper in Canberra will only be a good thing for the Brumbies and Australian rugby.

"I've created a good partnership here with 'Slipps' already that we had a couple of years ago (with the Wallabies) and it's good to see him back in Super Rugby," Sio told reporters.

"You don't play 80-plus Tests for Australia for no reason.

"It's a good challenge for me to keep competing and re-earn my spot in the starting team.

"I think as any rugby player would say you need a competitive environment to keep growing and learning and that's what I've been doing this year."

Sio was Wallabies coach Michael Cheika's pick as loosehead prop in their last Test of 2018, but Slipper could come into the frame for a third World Cup berth.

Australian Associated Press