The Brumbies have taken a major step towards winning Super Rugby's Australian conference with a 39-15 bonus-point win over the Jaguares in Buenos Aires.

Emerging fullback Tom Banks scored two tries in four minutes in the first half to set up a win that takes the Brumbies nine points clear of the NSW Waratahs with three games to play.

The Brumbies scored six tries to two, with replacement back Andrew Muirhead crossing for two in two minute late in the game in his second appearance.

The visitors trailed twice in the first quarter, but took control with Banks's brace.

He showed exceptional speed to zip through a hole after a back-row move from a scrum in the 25th minute.

Banks also showed plenty of toe when he won the chase to a kick from flanker Chris Alcock.

The 22-year-old former Queensland Reds back also threw the final pass for winger Henry Speight's second-half try.

It was a sixth loss in their past seven games for the Jaguares, who had hooker Agustin Creevy sin-binned on the stroke of halftime for coming in from the side.

The Brumbies dominated up front and also sparkled out wide in one of their most complete performances of the season.

Five-eighth Nicolas Sanchez gave the Jagaures first points with a third minute penalty, but the Brumbies hit the front after Carter crossed from one of their trademark rolling mauls.

The home team regained the lead when hard-running lock Tomas Lavanini crashed over the line.

But Banks's brace and a penalty from five-eighth Wharenui Hawera on the stroke of halftime gave the visitors a 10-point buffer at the break.

The penalty was awarded after Creevy was sin-binned.

The Brumbies didn't add any more points while Creevy was off, but Speight's try and Muirhead's double pushed the visitors clear before a late consolation five-pointer to Guido Petti Pagadizaval.