Despite Red Bull Racing not being tipped as favourite to succeed on the Valencia street circuit that hosts the European Grand Prix, Sebastian Vettel claimed the fastest time of the weekend so far in third and final practice.
The German swapped times with RBR team-mate Mark Webber through the heart of the hour-long session before emerging on top with a lap of 1min 38.052secs, over a second quicker than Ferrari's Fernando Alonso managed on Friday. Webber remained a threat to the end, eventually taking the chequered flag a couple of tenths adrift of Vettel, but was pushed back to third overall as Renault's Robert Kubica sneaked into second spot.
The Pole, a dark horse for qualifying after his previous street circuit showings in Australia and Monaco, wound up just over a tenth off the pace, while Adrian Sutil threw his hat into the ring for a qualifying surprise of his own with fourth place for Force India, the German the best Mercedes runner and ahead of Friday pacesetter Alonso.
Having dominated the opening session, Mercedes found itself further down the order than expected, with Tonio Liuzzi taking seventh in the second Force India ahead of Jenson Button, Lewis Hamilton, Nico Rosberg and Michael Schumacher, in ninth, tenth, eleventh and 15th overall. Last year's Valencia racewinner, Rubens Barrichello, added to the surprises by taking sixth spot for Williams, while Felipe Massa completed the top ten runners.
Heikki Kovalainen again headed the new teams in 19th spot, but was 1.7secs off the last of the established entries, Pedro de la Rosa's Sauber.