Ahead of today's second practice session the air temperature is 29 degrees C, while the track temperature is 38 degrees. It remains very hazy, the result, according to Narain Karthikeyan, because of the tyre burning facility nearby.

Sebastian Vettel topped the timesheets this morning in a session which at one stage saw the top three covered by just 0.010s. Jenson Button finished second quickest, ahead of Fernando Alonso, Lewis Hamilton and Mark Webber.

As ever, a number of reserve and test drivers were in action, while at Sauber Esteban Gutierrez stood in for Sergio Perez who is suffering from a heavy cold. Perez however, will take part in this afternoon's session having declared himself fit.

As has become the custom, we didn't see the option tyres this morning (soft) however, that will change this afternoon.

As we await the start of the session, Kovalainen complains that his brake pedal is "too long".

Kobayashi is first out, the Japanese followed by Vergne, who got this morning's session underway. They are joined by Kovalainen, Maldonado, Pic, Grosjean and Senna. Perez is another early riser.

Of the initial runs, Grosjean is quickest, the Frenchman posting 1:30.201. Still struggling for grip a number of drivers run wide.

Just seven minutes into the session Vettel is on track, the German posting 34.972 to go fourteenth. Next time around however, as Hulkenberg goes second overall (30.031), Vettel goes quickest in S1. However, a poor final sector (traffic) means he fails to improve.

Eight minutes into the session all but the Ferraris and Schumacher have posted times.

A 28.847 sees Webber go quickest, the Australian having said that he has no intention of playing second fiddle to his teammate in the run in to Brazil.

A couple of minor mistakes from Perez as he familiarises himself with the Buddh circuit. Or could it be the effects of his infection?

Button posts 28.548 to go to the top of the timesheets, ahead of Webber and Senna, only to be demoted when Vettel slips in a 28.064.

Alonso takes the top spot with a 27.785, the fastest time of the day, as teammate Massa encounters the kerbs. Subsequent replay shows the Brazilian enjoying an epic slide before taking to the air over the kerbs.

Currently sixth (28.582), Hamilton goes quickest in S1. He subsequently crosses the line at 27.762, just 0.010s quicker than Alonso's best. The Spaniard soon re-takes the top spot, purples in S1 and S3 helping as he posts 27.402.

Another big slide for Massa, the Ferrari momentarily disappearing in a cloud of tyre smoke as he uses too much of the kerb going into T12. As he gets going again he almost takes a Pirelli hoarding with him.

Grosjean spins at T11 and for a short while is stranded in the middle of the track before he is able to get going again. Like Massa, the Lotus driver uses too much of the kerb.

As Senna spins at T3, the result of carrying too much speed, Petrov is the first to switch to the softer (option) rubber. 62:36 on the clock.

Having gone quickest in the final two sectors, Vettel goes quickest overall (27.256), 0.146s quicker than Alonso. Hamilton is third, ahead of Senna, Webber and Massa.

Having posted a PB in S1, Rosberg admits that he's struggling for grip at the rear. "What should I do?" he pleads.

As the TV director focuses on (local hero) Karthikeyan, Petrov shows no sign of a significant improvement of the softs. On the other hand, Ricciardo, also on softs, improves to seventh with a 28.239.

As Hamilton is force to use the run-off at T6, Sauber tweets that Kobayashi has just completed a 20 laps run on a set of hard tyres.

Lots of activity in the Red Bull garage as mechanics work on the front suspension on both cars. Meanwhile, Raikkonen (softs) improves to third with a 27.507 as Rosberg and Schumacher also make the switch.

Now on softs, Grosjean goes second with a 27.397, as teammate Raikkonen goes quickest in S2 on his way to posting a 27.030 which is good enough for the top spot.