(GMM) Mark Webber drew first blood on Friday by going quickest in morning practice at the cold Nurburgring, as his Red Bull teammate Sebastian Vettel struggled.
Vettel, the dominant winner at Silverstone three weeks ago, was sidelined for much of the session when a minor electrical problem meant he had to abandon the RB5 at the side of the German venue.
When the German, wearing a modified helmet livery for this race, and the Red Bull were returned to the garage, a quick fix had him briefly back out on track but not yet on the pace at a home circuit he is nonetheless still to master in a formula one car.
Another local driver, Adrian Sutil, pulled out of the session in exactly the same place, on the exit of turn 1, with a loss of hydraulic pressure.
Four tenths behind Webber's best time of the session was the championship leading Brawn driven by Jenson Button. "Hopefully we can give Brawn a good run for their money this weekend," team boss Christian Horner told the BBC.
Ferrari's Felipe Massa was third fastest at the end of the 90-minute session, ahead of Jarno Trulli's Toyota.