Williams revived its tendency to impress the practice timesheets this year by dominating the second Friday session in Spain.

Williams revived its tendency to impress the practice timesheets this year by dominating the second Friday session in Spain.

The British team's Nico Rosberg and Kazuki Nakajima captured the top two spots at the Circuit de Catalunya, ahead of local hero Fernando Alonso.

Elsewhere, despite the abundance of major package upgrades throughout the field, Barcelona 2009 is proving business as usual: the Brawns and Red Bulls are quick, while grandees Ferrari, McLaren and BMW struggle.

The only glitch in that theory on Friday was the pace of the Toyotas, who after locking out the front row in Bahrain two weeks ago proved the tail-end of the practice order.

Also with glitches on Friday were Force India's Adrian Sutil, whose fuel pressure problem meant he didn't even change into his overalls, and Sebastien Buemi, who after five minutes was stranded at the side of the track with his brakes on fire.

The Swiss rookie, however, did get his Toro Rosso returned to the garage and back up and running.

Nelson Piquet's woes continued, after first escaping a light glance against the barriers and later narrowly managing to emerge from another gravel trap.

Friday's fastest Rosberg, meanwhile, ended the session watching his FW31 being lifted onto the back of a flat-bed truck, perhaps after running out of fuel.