Wallabies coach Dave Rennie on Friday said the Toomua and Queenslander James O'Connor were leading the Test five-eighth charge.

Against the Brumbies on Friday night at Leichhardt Stadium, Toomua started at No.12 for the first time this season, with Andrew Deegan at five-eighth and it worked a treat with the Rebels handing the Canberra team their first defeat with an emphatic 30-12 scoreline.

Toomua said the new combination made an impact, with their dual kicking game far superior to the Brumbies while they also made greater use of their talented backline.

But he admitted it took a bit of adjustment.

"I came in and I sat and the 10 locked, and then I was like, oh move over," Toomua said.

"It was a great selection call - you look at Deegs how he played - I thought we moved the ball better at the back there.

"I'll play the role that we need me to play."

While praising their intensity and physicality for the full 80 minutes, Melbourne coach Dave Wessels was a little annoyed they missed a bonus point with the Brumbies scoring a last-ditch try.

Wessels said the Rebels were motivated by those left behind in Melbourne and were determined not leave the competition empty-handed.

The Rebels have now been on the road for seven weeks, and unlike AFL and NRL teams, don't have their families in hotel hubs with them.

Wessels is a father of three young children who he has left behind in Melbourne.

"I spoke to someone in Victoria and they genuinely sounded really down and I think the motivation for boys that everyone at home is doing it pretty tough," Wessels said.

"There's a huge motivation in the group to want to play for those people, particularly our families and the staff back home.

"We are really motivated to make them proud."

Australian Associated Press