Last year's winner Nico Rosberg led Lewis Hamilton in a Mercedes one-two at the top of the timesheets after first practice session of the Chinese Grand Prix on Friday.
Hamilton, the 2008 world champion was almos half a second slower.
Red Bull's Mark Webber, was third with teamate and world champion Sebastian Vettel fourth.
Triple champion Vettel leads the championship after two races with 40 points, nine clear of Lotus's Kimi Raikkonen.
