Villeneuve believes the Sauber team face a difficult season

The Swiss outfit have made progress in recent days but the car still has problems, the Canadian said.

"We are still slow, but it is better because we were very slow last week. Now we are just slow," Villeneuve told the website of Autosport magazine.

He also said he was having trouble adapting to the car from the Renault he drove in the last three races of 2004.

"Everything on this car is different to the 2004 Renault, even the suspension. I even have to adjust the way I change things on the car," Villeneuve said.

"The electronics for the brakes seem to be different to what I was used to and I will have to adjust my driving style.

"I don't think the team can change it to adapt to me. Probably a rich team can change the things to suit the driver, but probably here I will have to change."

The 32-year-old added that the car was struggling to get the benefit of fresh tyres, which usually provide a speed advantage on the first couple of laps.

"The car seems to be better with old tyres," Villeneuve said. Villeneuve joined Ferrari-powered Sauber on a two-year contract at the end of 2004 after driving the last three races for Renault as a replacement for Italian Jarno Trulli.

He failed to score any points but before that the Canadian had been out of action for almost a year following his departure from BAR in October 2003.