First-year Brumbies Zack Holmes and Ian Prior will guide their team around the field when they take on the Hurricanes tomorrow night.

It's the fourth flyhalf-scrumhalf combination the Brumbies have used this season.

Holmes will call the shots in the No.10 jersey as well as taking on the kicking duties, while Prior gets his chance to step up with Nic White being rotated to the bench.

It will be the duo's biggest challenge, but while Nic White, Christian Lealiifano and Matt Toomua spent time forming combinations together, Holmes and Prior formed a partnership on the opposite side at training.

Holmes has played just 40 minutes of rugby from the bench in his debut season, but Jake White said the 21-year-old was the ''logical'' choice to replace Lealiifano.

''The logical thing is a guy like Zack who has run a lot more with Ian Prior in the other group and it's quite nice he gets to play with Ian as well,'' White said.

''The thing I like about him is he's not scared to take it to the line … it's a difficult one for him because he has a lot of key roles but that's part of the position he plays and I'm sure he will be good enough to take it.''

The Brumbies sit at the top of the Australian conference and can maintain their buffer if they beat the Hurricanes.

Holmes gets his chance to shine after Christian Lealiifano broke his ankle two weeks ago.

Holmes started the season on the bench, but had to wait until the third game of the year before he finally got on the field.

But the former Australian Sevens representative's goal-kicking ability and extended training time at flyhalf helped him win the race to be Lealiifano's replacement.

''It has come a little bit earlier than expected,'' Holmes conceded.

''I will just play what we've been going through since July last year and I've almost been running the plays for a year now.

''It's just making sure of when I get there I'm aware of everything I need to do.''