Brawn: Williams, Michelin may cause us problems

The Grove-based team's 2001 package, including a BMW engine that revs to over 18,000rpm - more than all its rival - and is rumoured to produce more bhp than even a Mercedes unit, has already run Ferrari close in qualifying in Malaysia. But Brawn believes it is the Michelin factor that could be key to moving Williams into the premier league on a race-by-race basis.

"Williams could prove to be up there this year because of tyres," Brawn told Autosport's sister publication . "We're on the same tyres as McLaren, so that has an equalising effect. But there could well be a number of occasions when the Michelins are very strong and the Williams will be a pain."

The Williams team is relishing the prospect of taking on Ferrari and McLaren in the heat of Brazil, but the team's technical director Patrick Head admits to being a little surprised at just how strong the BMW engine is this year.

"We had no idea that the BMW engine was going to be so powerful," he said. "The evidence now is that BMW is at least as strong as any other engine out there, and possibly stronger.

"What they've done is pretty impressive at the beginning of their second year in F1," he added. "But our performance is going to depend enormously on the tyres."

BMW motorsport chief Gerhard Berger said: "It's just as impressive for Michelin to be able to be in that position in only its second race. The whole package is fitting together."