Peter Sauber, the former team boss who introduced both of Ferrari's current drivers to Formula One, sees the Italian team suffering this season following the departure of Michael Schumacher.

"I think after Michael it will be a difficult year for Ferrari," the Swiss, who sold his Ferrari-powered team to BMW in 2005, told reporters at the launch of the new BMW-Sauber car on Tuesday.

"He was an excellent driver, not only fast but especially on the technical side.

"But on the other hand, I'm sure (Ferrari team boss) Jean Todt knows exactly how good Kimi (Raikkonen) is and where his strengths and weaknesses are.

Finland's Kimi Raikkonen, who made his grand prix debut with Sauber in 2001 after the team convinced the sport's governing body to grant him a superlicence, has replaced seven times world champion Schumacher at Ferrari.

His team mate will be Brazilian Felipe Massa, whose first F1 race was for Sauber in 2002 after Raikkonen left for McLaren.

"Jean Todt has been a big fan of Kimi for many years...he knows the weak side of Kimi, especially on the technical side," said Sauber.

"Kimi is not so interested in technical things and today in Formula One that is very important, to develop the car," he added.

"But I think he has good support in Felipe. Felipe made a good step forward last year."

Massa won two races for Ferrari last season, including his home Brazilian Grand Prix.