Button future champ says Berger

Berger, who is the director of motorsport for BMW, has witnessed Button's meteoric rise to F1 stardom this year first hand. The veteran of 210 GPs tipped the 20-year-old as a potential world title contender when he returns to Williams after a two-year loan to Benetton while speaking at the BMW end of season party.

"It will be difficult to see him in another team next year," said Berger, "but he is still young and he can still improve. That is good for us because I understand Frank [Williams] has a long-term deal with Jenson and I wouldn't be surprised if one day you see Jenson Button as world champion."

Button had his first run with the Benetton team at Jerez last week driving this year's B200 car fitted with traction control, in preparation for the likely return of the banned driver aid next year (see separate story). Button said he was unsure of the device, which prevents wheelspin, but was all for equality along the pitlane.

"It will be difficult now to go to traction control," said Button. "I'm not sure how different it will be, but I suppose it will be better because we will be on the same playing field."

F1 testing continues this week with Benetton joining the other Michelin-shod teams at the circuit de Catalunya in Barcelona, while the Bridgestone faction are further south at Valencia.