Vettel was confirmed at the Hungarian Grand Prix as one of the Ferrari-powered team's drivers for 2008 as well as the remaining seven races of this season in place of dropped American Scott Speed.

German seven times Formula One Champion Michael Schumacher smiles as he walks past some fans prior to the European Formula One Grand Prix at the Nuerburgring racetrack, Germany, Sunday, July 22, 2007. [AP]

"I was one time in Mauritius on holiday and Michael Schumacher came to me," Austrian Berger told a news conference at the Hungaroring, where the 20-year-old German will make his team debut on Sunday.

"He said 'Gerhard, you have to look. There is this guy in go-karts, the name is Vettel.' I said 'Who?' 'Vettel, he is very quick.' And that was many years ago."

Vettel, who in June became the youngest driver to score a point in Formula One when he stood-in for Poland's Robert Kubica at the U.S. Grand Prix, was the BMW Sauber test and reserve driver until this week.

He was the immediate choice when Californian Speed fell out with Toro Rosso after the European Grand Prix.

Berger said Speed, who declared after the Nuerburgring that no amount of money would persuade him to race for Berger again, had not performed. However he said he could still have a role as test driver.

"Lately we didn't have a good atmosphere, and I don't want to say it's all Scott's fault, or our fault," continued Berger. "But it just didn't work out and the only way is to stop it.

"We are very happy with Sebastian and we think we are going to have a good relationship, no problem.

"I think it's great to have a young spirit in the team again, when I watched him and followed him I could see a great commitment. He's intelligent... the speed I hope is going to show that he's quick."

Vettel recognised that Toro Rosso, who have yet to score a point this year, were a far cry from third-placed BMW.

"The car is not as strong as the top cars in front and there is a lot of work to do but I think I can bring some motivation to the team and try my best to improve the situation and then finally get some points," he said.

Toro Rosso have yet to name their second driver for 2008, although France's triple ChampCar champion Sebastien Bourdais is a strong contender to replace Italian Vitantonio Liuzzi.