A group of part-time rugby players stepped up in a team boasting 11 ACT Brumbies as Canberra beat the Greater Sydney Rams 37-18

Brumbies flanker Jarrad Butler scored a double and the Vikings scored 29 unanswered points to secure their first win of the new third-tier competition.

Wallabies hopeful Christian Lealiifano was attempting to push his case for Test selection, but the talented playmaker barely saw the ball in a slippery game.

In fact, Lealiifano handed the goal kicking duties to Jesse Mogg after admitting last week his inaccuracy with the boot this year had dented his confidence.

"We just wanted to let Christian play, not over-complicate things," said Canberra coach Dan McKellar.

"Get confidence through his carry and defence and not have to worry about kicking.

"It's not a long-term thing, it was just for tonight and Moggy has been hitting them well, so that's the direction we went in."

Canberra's Super Rugby contingent was expected to be the difference

but the Brumbies representatives took a back seat as players like Les Makin, Seilala Lam, Isaac Thompson and Tim Cree took the reins as Canberra erased a horror start to storm to the lead.

Lealiifano struggled to get into the game, while Mogg had a mixed night as he attempts to recapture his best form.

Fullback Mogg got off to a disastrous start, slipping when trying to clean up a loose ball on his own line, which allowed the Rams to score their second try.

But he looked dangerous when he ran the ball and his goalkicking was impressive.

The Vikings dropped the ball from the kick-off, then conceded two tries and Lam was sent to the sin bin as the Rams had more than 70 per cent of possession in the first 20 minutes.

Butler crossed twice in the second half as the Vikings dominated the set piece and Jordan Smiler showed superb desperation in defence.

The Brumbies still have four contract spots up for grabs for the 2015 Super Rugby season and coach Stephen Larkham is searching the NRC for new recruits.

"We back our depth, we've got the squad and the club guys are there for a reason," McKellar said.

"Isaac is always improving and he went straight through a gap for the first try, our forwards dominated the set piece and really got us going.

"It was a bit of a mixed night but I think we finished the first half on top and that gave us some momentum."

Australian sevens star and Commonwealth Games medallist Tom Cusack scored in the second half in his first 15-a-side game in 12 months.

Cusack was on the verge of winning a Brumbies contract last year before rupturing his anterior cruciate ligament in a club game for Royals, and was instead signed by the Australian sevens team.

Barnstorming prop Les Makin put the Vikings in front just before half-time when he barged through defenders to score and Mogg converted to give Canberra a 16-10 lead at the break.

CANBERRA VIKINGS 37 (Jarrad Butler 2, Isaac Thompson, Les Makin, Tom Cusack tries; Jesse Mogg 4 cons) bt GREATER SYDNEY RAMS 18 (Vasa Falealifii, Atieli Pakalani, Jed Holloway tries, Ben Volavola con) at Parramatta Stadium on Thursday night.