Red Bull driver Sebastian Vettel set the fastest time in today's opening practice for the Indian Grand Prix, boosting his hopes of taking a fourth successive race win and extending his Formula One championship lead.Vettel was three tenths of a second faster than McLaren's Jenson Button, while his chief title rival Fernando Alonso of Ferrari was third fastest.McLaren's Lewis Hamilton was fourth on the time sheets, ahead of Red Bull's Mark Webber, while Lotus' Kimi Raikkonen – the only other driver in title contention – was in 10th.Sauber's Sergio Perez sat out the session with flu-like symptoms, but the team expected him to be fit to take part in second practice later toiday. He was replaced by Mexican compatriot Esteban Gutierrez.