Circuit for Indian GP is challenging: Red Bull drivers

Vettel will go into the October 28 race with a six point lead over Ferrai's Fernando Alonso.

"I loved the track layout last year, but not just because I won the race. With an average speed of 235kph, the course is the second quickest of the year after Monza.

"There is a lot of elevation change around the lap which adds to the fun, from as much as 8% downhill and up to 10% uphill; it