Title defeat will make Vettel stronger - Stewart

Sebastian Vettel is too young and immature to win the 2010 world championship.

That is the claim of 71-year-old Sir Jackie Stewart, who won his first of three drivers' world championships in 1969 at the age of 30.

When asked about 23-year-old German Vettel's chances of winning the title this year, Scot Stewart told Auto Motor und Sport: "He is too young for the world championship.

"He has all the time in the world to do it, and he will. The defeat will make him even stronger for 2011," he said at Interlagos.

"I can't even remember when I was 23 years old. You're far too immature for the title.

"I was 30 when I became champion for the first time, and 34 when I won my last one. And I can tell you that I was a better champion when I was 34," said Stewart.

He also advised Red Bull to take a strategic approach to the last two races of 2010.

"As a team boss, in their situation, I would say that the constructors' title is virtually in the bag. If I wanted the bonus of the drivers' title, I would put all my chips on Webber," said Stewart.