Ahead of today's all-important qualifying session, the air temperature is 30 degrees C, while the track temperature is 38 degrees.

It was business as usual this morning with Sebastian Vettel leading the way from Jenson Button, Mark Webber, Lewis Hamilton, Fernando Alonso and Felipe Massa. However, Paul di Resta was the best of the rest, heading the Mercedes', Toro Rossos, Renaults and Saubers.

Massa was quickest yesterday, the Brazilian running a controversial front wing that vibrates violently and scrapes the ground. Although the FIA has given it clearance - no pun intended - the Ferraris set their best times this morning with a different wing.

Unusually, the prime tyre this weekend is the softer rubber with the harder compound being designated the option. It's thought there is as much as 2s between the two and as a result we could see a very strange session this afternoon with a number of drivers opting not to run in Q3 in order that they can start tomorrow's race with the option (hard) tyre and subsequently dump them as soon as possible.

However - and there's always an however in F1 - with such a difference, even the leading teams may need to dip into their stash of softs as early as Q1 leaving them short for the race. In others words, strategically, we could be in for an intriguing session.

Then again there's the circuit itself with a green and very dusty surface that continues to catch out the best of the drivers and some substantial unforgiving run off just the other side of the equally harsh kerbs.

While both titles are decided there is still plenty to fight for in terms of the Drivers' Championship and also the Constructors' Championship, the latter, of course, deciding who gets what prize money.

Having secured pole in Korea, Lewis Hamilton has no hope of repeating the feat today, the Englishman, like Sergio Perez, having incurred a three-place grid penalty for ignoring waved yellow flags at the end of yesterday's opening session. At HRT, Ricciardo has been given a five-place penalty after changing the gearbox on his car.

The lights go green and Kovalainen leads Petrov, Trulli and d'Ambrosio.

As Kovalainen posts 1:32.814, more and more drivers pour on to the track, all of them on the harder rubber.

No sooner has Petrov posted 30.347 than his teammate ups the ante with a 29.952. Sutil splits the Renaults with a 30.202. All but the Saubers on track.

Petrov goes quickest with a 29.035 but moments later he is leapfrogged by Alonso who crosses the line at 27.836. Massa goes second with a 28.281 and Hamilton third on 28.594.

Vettel's first lap sees the German go third (28.493), while Buemi goes fifth ahead of Petrov and Alguersuari.

Alonso retakes the top spot with a 27.478, the Spaniard having been quickest in the first two sectors.

Webber goes straight into second place, the Australian stopping the clock at 28.161 as Barrichello goes off kicking up a great cloud of dust.

Button posts 27.978 to go second but Vettel and Hamilton are both on hot laps. Webber goes quickest (27.410) but in the moments that follow Hamilton and then Vettel go quicker (26.948).

With 10:14 on the clock, the Saubers have yet to make an appearance.

Massa goes quickest in S2, subsequently crossing the line at 27.012 to go third. Elsewhere, Schumacher makes a mess of the final corner.

Button goes quickest in S1, watched by Glock who is out of his car, sidelined by gearbox failure, and watching the action on TV.

A 26.774 sees Alonso go quickest, however, Hamilton beats it with a 26.563 only to be beaten by Vettel's 26.218.

As the Saubers finally leave the pits, on softs, they, along with Lotus, Virgin and HRT remain in the danger zone. The Williams duo is hovering just above.

Button, now down in seventh, complains that he has no grip. Elsewhere, Webber makes it a Red Bull 1-2 when he posts a 26.473.