Sebastian Vettel showed he has the pace to win a fourth straight Formula One race and pad his thin championship lead by setting the fastest time in Friday's practices for the Indian Grand Prix.

Vettel headed a Red Bull one-two in the second practice, with teammate Mark Webber a tenth of a second behind.

Ferrari's Fernando Alonso - Vettel's title rival, just six points behind - was third fastest, six-tenths off the pace.

Red Bull locked out the front row in qualifying for the previous two races and the times here indicate a hat trick is in the offing.

"The track improvement was quite big today, it was dusty to start and improved lap by lap, so I wouldn't be surprised if tomorrow the order is different, but we've had worse Fridays, so I am happy," Vettel said.

Alonso was banking on the evolution of the track over the race weekend to perhaps bring Ferrari up to Red Bull's speed.

"The track conditions, which change rapidly lap after lap, make it even more complicated to understand the situation relating to the hierarchy down the pit lane," Alonso said.

McLaren lagging

Lotus' Kimi Raikkonen, who had not even sighted the track on a simulator before, was fifth fastest ahead of the McLarens of Lewis Hamilton and Jenson Button, as all the championship contenders proved competitive.

"We're probably quick enough to qualify third or fourth fastest at the moment, but, to go for pole, we're going to really need to push hard in our development work tonight," Hamilton said.

Mercedes' Nico Rosberg was fourth on the time sheets, shortly before all the major runners switched to higher fuel loads to simulate race running.

"We're probably quick enough to qualify third or fourth fastest at the moment, but, to go for pole, we're going to really need to push hard in our development work tonight"

McLaren driver Lewis Hamilton

Force India's Nico Hulkenberg set the eighth fastest time, followed by Lotus' Romain Grosjean and Williams' Bruno Senna.

The track was predictably dirty after a year without racing, but as the rubber got laid down, times improved; Vettel's time in the afternoon practice was 1.4 seconds faster than his morning time.

Ferrari's Felipe Massa struggled with the limits of the track more than the others, with two spins in the afternoon, including one where he had the ignominy of colliding with an advertising hoarding while trying to drive away from the scene. Massa had a series of spins at this track last year, too.

Button also had a difficult afternoon, sitting out the latter part of the session due to a transmission issue with the car. Button did not finish the previous race, so he can change his gearbox without any grid penalty.

Sauber driver Sergio Perez sat out morning practice due to the lingering effects of a cold but took part in the afternoon. In the morning he was replaced by his Mexican compatriot Esteban Gutierrez, who is widely tipped to get the seat on a permanent basis next year when Perez moves to McLaren.

Source: AP