Fernando Alonso topped the final practice session ahead of qualifying for the Bahrain Grand Prix as Red Bull's Sebastian Vettel failed to set a quick lap on medium tyres but still finished second.
Alonso's time of 1:33.247 was 0.101s faster than Vettel's time with Mark Webber third and Kimi Raikkonen fourth. Alonso improved by 0.4s on the medium tyres, but when Vettel came to set his fast lap he came across Charles Pic's slow-moving Caterham in the final corner and decided to back out. As a result it is hard to gauge how much quicker the Red Bull would have been, but assuming Vettel could have found a similar advantage from the softer rubber he would have gone fastest.
The session wasn't completely straight forward for Alonso, who had an uncharacteristic spin as he got on the power coming out of turn two. It looked like he simply applied too much throttle on corner exit, but despite ending up in the gravel he managed to continue with his session.
Of greater concern, Lewis Hamilton suffered what appeared to be a de-lamination of his left rear tyre on his final lap. Going along one of the straights the tyre appeared to come apart and the force damaged his rear suspension, giving the Mercedes mechanics work to do ahead of qualifying. The exact reason for the tyre issue is unknown with Pirelli technicians on the scene as the car returned to the pits. Hamilton had managed the fifth fastest time, 0.208s off Alonso, but set his first medium tyre lap a little earlier in the session than his rivals.
Romain Grosjean showed signs of recovery from his difficult start to the season with the fifth fastest time and was only 0.018s off Kimi Raikkonen, who lost time in the middle sector on his fast lap. Adrian Sutil and Paul di Resta continued Force India's strong weekend with the seventh and eighth fastest times ahead of Nico Rosberg in ninth and Nico Hulkenberg in 10th.
Felipe Massa finished the session just outside the top ten and 0.702s off his Ferrari team-mate, with the two McLarens of Jenson Button and Sergio Perez 12th and 13th as it looks increasingly likely that they will struggle to make Q3 in qualifying.