Impressed with Vettel's performance: Kaltenborn

Sauber team principal Monisha Kaltenborn Sunday said she is impressed with the way newly-crowned four-time Formula 1 drivers' World Champion Sebastian Vettel has utilised his potential over the years.

One must not forget that the 26-year-old German, who won the championship at the Indian Grand Prix here Sunday, started his career at Sauber in 2006 when he was a reserve driver. Vettel raced in his first Grand Prix in the United States in 2007 for Sauber before making a switch to Toro Rosso.

"His performance over the last four years has been very impressive. We know him a little from when he started in Formula 1.

"Obviously one could see how talented he was and how much potential he had in him. That is one thing to have and the other thing is actually to utilise it and to build it further, which he has shown together with his team in a very impressive way," the Indian-origin Kaltenborn told IANS at the Buddh International Circuit.