Ahead of today's sole practice session, the air temperature is 25 degrees C and the track temperature is 27 degrees. It is already warmer than yesterday and its going to get a lot hotter.

While yesterday's sessions, which saw Pastor Maldonado quickest in FP1 and Sebastian Vettel leading the way in FP2, were noticeable for the amount of lock-ups and offs, it was also clear that McLaren has a bit of a problem here.

Jenson Button, who is copying his teammate's set-up for once, finished the day twelfth quickest overall while Lewis could only manage fourteenth, the 2008 world champion subsequently admitting that his team is struggling.

Although Red Bull is looking worryingly good here, suggesting that Vettel could be on for his third straight win, the Ferraris, Mercedes, Force Indias and Williams also impressed.

What was noticeable in both session is how close the field is, in the first session the top nine were covered by around 0.3s while in FP2 it was 0.4s that covered the top seven. With overtaking so difficult here qualifying will be crucial.

Tyre options this weekend are medium (prime) and soft (option), Pirelli reckoning that there is around 0.3 to 0.5s between them. That said, this could, and no doubt will, change as it gets hotter, particularly tomorrow.

The lights go green and di Resta leads Kobayashi, Vergne, Kovalainen, Ricciardo and Petrov as the second day of the Valencia weekend gets underway. Within three minutes all but Hamilton and Hulkenberg have been out for an installation lap, Alonso drives at a leisurely pace, waving to the fans in the stands.

While everyone is on the prime tyre we can expect to see the options getting put through their paces this morning in anticipation of this afternoon's all-important qualifying session.

While Maldonado and Kobayashi stay out for a second installation lap, there is no urgency, and once they return to the pits all is quiet for several minutes. Eventually, ten minutes into the session, Grosjean breaks the deadlock and heads down the pitlane. Moments later he is joined by his Lotus teammate.

The cameras cut to the paddock where Jean Todt, Luca di Montezemolo and Ross Brawn are in conversation.

Grosjean crosses the line at 1:40.136 as Webber, Rosberg and Hamilton leave their garages. Moments later Raikkonen posts 40.621.

Hamilton splits the Lotus duo with a 40.324, he would have gone quickest but for a poor final sector. Moments later a 40.216 sees Raikkonen re-take the second spot. Perez goes fourth, ahead of Vergne, Ricciardo, Karthikeyan and Hulkenberg.

Maldonado goes third, having gone quickest in S3, however, Hamilton, who gores quickest in S1 is on a hot lap. That said, the McLaren driver subsequently loses time in the second sector after a lock up in turn 12.

A 39.796 sees Raikkonen go top as Button posts 40.537 to go sixth. The Red Bull and Ferrari drivers resolutely remain in their garages.

Hamilton goes quickest with a 39.793 as teammate Button improves to third. Elsewhere, Webber and Vettel leave the pits.

Hulkenberg goes fifth, ahead of Maldonado, Schumacher, di Resta and Perez. The top eight is covered by 0.551.

The Ferrari duo finally leave the pits around twenty-five minutes into the session. However, while Massa stays out on track, teammate Alonso returns to the pits after the one lap.

Vettel goes third (39.911) but is immediately demoted when a 39.762 sees Maldonado go quickest.

Vettel goes quickest in S1 while Massa goes eighth overall, crossing the line at 40.142. Vettel improves to 39.823 but remains fourth. Elsewhere, a massive lock-up for Petrov.

Ni mistakes for Vettel next time around, the German going quickest with a 39.448. However, at 28:30 all eyes are on Grosjean, the Lotus driver being the first to switch to the soft rubber. After a quick check, Alonso is back on track.

Massa improves to third with a 39.772 however, Vettel is already on a hot lap, as is Grosjean.

Unsurprisingly, Grosjean is quickest through all three sectors, crossing the line at 38.655, 0.779s quicker than Vettel.