By NESHA STARCEVIC, Associated Press
NUERBURGRING, Germany (AP) — Mercedes drivers Lewis Hamilton and Nico Rosberg dominated the first practice for the German Grand Prix on Friday, and the new tires supplied by Pirelli held.
Leading drivers have threatened to withdraw from Sunday's Formula One race if tire problems persist, while teams were asked to stick to operating requirements.
Hamilton set the pace in practice, completing the fastest lap in 1 minute, 31.754 seconds. Hamilton is still seeking his first win since joining Mercedes this season.
Rosberg, winner of two of the last three races, was .219 seconds behind. Red Bull's Mark Webber was third and Force India's Adrian Sutil was fourth.
Championship leader Sebastian Vettel, still looking for his first win on home soil, was eighth fastest. His closet challenger, Fernando Alonso, failed to complete a lap in his Ferrari, apparently due to electrical problems.
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