Brawn flex their muscles in Valencia

After three below-par races during which the Brawns have struggled for grip, a number of revisions made to the BGP 001 for this weekend appear to have had the desired effect, with championship leader Jenson Button taking second and Rubens Barrichello third.

The Brawns were in fact switching between two different set-ups in their effort to rediscover their early-season form, which saw Button win six of the first seven races.

The team began the session running the car in the form it contested the Spanish Grand Prix in May, and ended it in the specification used in Hungary last time out.

More crucially for Brawn, their nearest challengers in both the drivers' and constructors' championship - Red Bull - had a miserable session.

Mark Webber, second in the championship to Button, finished down in 14th, while Sebastian Vettel claimed ninth.

With the track temperature around 10 degrees up on the morning and the dust having largely cleared from the winding street circuit, times were significantly improved.

Alonso's best was a scorching one minute 39.404 seconds, three seconds better than Barrichello's pace-setter during the morning, and seven tenths faster than Button's quickest effort in the afternoon.

Williams continued to impress in the Valencia sunshine, Friday practice specialist Nico Rosberg taking fourth ahead of team-mate Kazuki Nakajima, while Force India's Adrian Sutil did a sterling job to replicate his sixth place from the morning.

McLaren's Lewis Hamilton sat out the bulk of the session following an early spin which left him with damaged front wing supports, although the problem is expected to be resolved for qualifying.