The Brumbies are top of the Australian conference with four games to play and can jump into second spot on the overall ladder when they host the Bulls on Friday night.

Sio is in career-best form thanks to the arrival of fellow Test prop James Slipper, and penned a new three-year deal with the Brumbies this week.

The 27-year-old said he considered leaving Australian rugby but opted to stay in pursuit of winning Super Rugby and the World Cup.

"I haven't won a Super Rugby championship yet, or a World Cup. They're two massive dreams of mine and I can only do that if I'm plying my trade here," Sio said.

"We've got four games to make the most of it and we're in a really good position. To be in the driver's seat is great and it forces us to go up another level.

"We've just got to keep winning, win seven games and you win Super Rugby, it sounds easy but we've got a big task ahead of us."

Wallabies veteran Slipper and Sio have been playing loosehead in tandem this season which has brought new life into both player's game.

Sio believes the combination has produced his career-best form.

"I think so. The last two years were ok and I got by on some good performances.

"But as you go through your career you want to be replicating great performances," Sio said.

"I've known Slips for a very long time now, we went to a World Cup together and have shared many Wallabies tours together, I saw (his arrival) as an exciting prospect.

"He provided fierce competition for the loosehead spot that maybe we haven't had in a long time here, and an opportunity for me to get better.

"I learn from him and hopefully he learns from me, that's what we've done throughout the season and built a great partnership.

"We're very competitive so we'd both love to start every week, but we understand the role we're playing for the team and it's helping us get results."

Australian Associated Press