Evan Roos warns form counts for little as Stormers brace for bruising Bulls derby

The Stormers are sitting pretty at the top of the URC table, while the Bulls are struggling for form, but Roos expects a fierce battle between two of South Africa's traditional rivals nonetheless.

"It's going to be physical, obviously," Roos said. "It's a north-south derby and South African players are always up for it. The guys always step up in an amazing way when these two sides play against each other.

"We're excited, it's going to be awesome and I'm happy to be part of it."

The Stormers head into the match on a nine-game unbeaten run in the URC, with Roos crediting their consistency to clear objectives and disciplined execution.

"Every team wants to do as well as they can in the URC," he said. "I think we stuck to what we wanted to do and did it well and the results have paid off so far.

"It's now just up to us to keep on driving our own standards and trying to be better every game."

Saturday's derby also features a heavyweight loose-forward contest, with Roos likely lining up against Bulls forward Elrigh Louw - one of his main rivals for the Springbok No 8 jersey. However, Roos was quick to play down any talk of personal duels.

"Those things don't get me up," he said. "If you go into a match with that kind of mentality, then it's actually quite a selfish thing to do.

"For me, personally, I just want to do what the team requires of me this weekend."

Saturday's north-south derby between the Stormers and Bulls kicks off at 6pm.