SILVERSTONE, England (AP) - Mercedes driver Nico Rosberg was fastest in practice at the British Grand Prix, followed by the Red Bull drivers Mark Webber and three-time defending champion Sebastian Vettel on Friday.
Rosberg, who won the Monaco GP, was 0.299 seconds faster than Webber. The Australian surprised his team on Thursday by announcing he would be leaving Formula One at the end of the season to race sports cars.
Vettel was 0.432 seconds behind as he looks to extend his lead atop the drivers' championship.
The German has a 36-point lead over Ferrari's Fernando Alonso with 12 races remaining. Lotus driver Raikkonen is another eight points back in third and Mercedes driver Lewis Hamilton is fourth.
Hamilton was the closest among Vettel's rivals, coming in fifth fastest.