Sebastian Vettel topped the timesheets at the end of second practice for the Spanish Grand Prix as he edged out Fernando Alonso by just 0.017s.
With Red Bull not showing its pace in the morning session - when Vettel and Mark Webber were 19th and 20th respectively - the pair traded fastest times with Alonso early on before the medium tyre runs saw all three drivers covered by 0.083s. Kimi Raikkonen was also a close fourth, with his time of 1:23.030 leaving him just 0.222s behind the pace-setting Red Bull.
In a tight session, Felipe Massa was fifth and Lewis Hamilton sixth; Hamilton just 0.332s off the quickest time. It wasn't a completely smooth session for Hamilton, though, as he had to recover from a spin at Turn 12 early on.
The Force India and Toro Rosso drivers were closely matched, but there was a worrying moment for Paul di Resta and Pirelli as the Force India's left rear tyre shed its tread, exposing the carcass underneath. Di Resta stopped his car near the pit exit, allowing it to be pushed back in to the pit lane while Pirelli was quick to cover up the delaminated tyre.
Having completed a total of 12 laps in the morning session when spray would have affected its sensors, McLaren had a more productive afternoon as it analysed its updated MP4-28. Jenson Button took just seven minutes of FP2 to set his first time of the day and was 12th quickest, with Sergio Perez one place behind his team-mate, albeit two seconds off the pace.
Romain Grosjean was out of position in 18th fastest after failing to set a quick lap on the medium tyres. He was only a tenth clear of the updated Caterham of Giedo van der Garde, which held a 0.05s advantage over Jules Bianchi's Marussia.