Rosberg leads first practice in Valencia

Nico Rosberg was fastest in the first practice session for the European Grand Prix.

The Mercedes driver led the McLaren pair of Lewis Hamilton and Jenson Button after a session which was interrupted by a red flag.

Reserve drivers Paul di Resta and Christian Klien drove during the session.

Bruno Senna lost a wing mirror from his HRT in the first half of the session. It was hit by a couple of cars, including Sebastien Buemi and Heikki Kovalainen, and the session was briefly stopped so marshals could clear the debris from the track.

Several teams tested major upgrades to their cars including Ferrari, Mercedes and Renault – all running their exhaust-driven diffusers for the first time – and Red Bull – who were evaluating their version of the F-duct.

The track was also very dusty and several cars ran wide at the first corner, taking to the escape road to avoid hitting the barriers.

Mistakes became more frequent as the session went on and drivers’ tyres became increasingly worn. Jaime Alguersuari was heard on his team radio saying the tyres were “destroyed”.

Lotus strugged with graining on their front tyres, particularly the front-left. Despite that Heikki Kovalainen was the fastest of the new teams, within one second of Alguersuari.

McLaren led the way to begin with and were half a second quicker than their rivals for a large part of the session.

Rosberg beat Hamilton’s time while testing Mercedes’s F-duct, setting the quickest time while running their rear wing stalling device.

Two teams ran reserve drivers during the session. Paul di Resta appeared for Force India in Adrian Sutil’s place, and Christian Klien took over from Karun Chandhok at HRT. The regular drivers are expected back in the cars in second practice this afternoon.

2010 European Grand Prix