Mark Webber was comfortably quickest in first practice for Sunday's European Grand Prix as Red Bull Racing clearly adopted different strategies with their drivers.
Around the 25-turn Valencia Street Circuit that meanders its way through the port built for the 2007 America's Cup, Webber finished more than 0.8 seconds clear of his rivals after the 90-minute session.
The Australian posted a lap of one minute 40.403secs, with Vitaly Petrov in his Renault and Ferrari's Fernando Alonso second and third, the duo separated by just 0.012secs.
McLaren's Lewis Hamilton, aiming for a clean weekend following his travails in the last two races in Monaco and Montreal, was fourth, but 1.107secs adrift of Webber, with the second Renault of Nick Heidfeld completing the top five.
As for reigning champion Sebastian Vettel, who leads the current standings by 60 points, the 23-year-old was on an alternative programme as he finished down in 16th, 2.538secs behind Webber.
Ahead of him in the top 10 were Ferrari's Felipe Massa and Jenson Button in his McLaren, followed by Adrian Sutil in his Force India and the Mercedes of Nico Rosberg, with Jaime Alguersuari in his Toro Rosso 10th, the Spaniard 1.813secs down.
It was not a good day for two of the sport's reserve drivers, with Force India's Nico Hulkenberg losing his car under braking on the approach to turn 12 after 22 minutes.
Hulkenberg, standing in for Paul di Resta, slithered his way along the dusty track before first crunching the nose of the car into a wall and then the left-rear wheel, forcing him to retire.
For Team Lotus reserve driver Karun Chandhok, first practice was yet another unhappy affair for the Indian.
Chandhok's maiden outing in Australia ended inside the first minute after being the first to take to the track at Albert Park as the 27-year-old speared the car into a wall.
Then in Turkey the atrocious weather conditions saw him manage just six laps and finish 13 seconds off the pace.
In being given another chance here, Chandhok was again a frustrated figure as the car on this occasion lost second gear on his way out of the pits, leaving him propping up the standings without a time to his name.
Unfortunately for Chandhok and Lotus, a spare was unable to be fitted as it had not arrived in time from suppliers Red Bull, with technical director Mike Gascoyne describing the situation as "very disappointing".
Chandhok's compatriot, Narain Karthikeyan, was the last of those with a time, finishing 6.5secs off the pace for Hispania.Reuse content