Austin: Nico Rosberg made a determined first move towards wrecking Mercedes teammate Lewis Hamilton’s Texan title party when he topped the times in opening free practice for this weekend’s United States Grand Prix.

The 30-year-old German, who has to prevent Hamilton beating him by three points in tomorrow’s race at the Circuit of the Americas to keep his own challenge alive, clocked a best lap of one minute and 53.989 seconds on a damp, drying track.