Mercedes proved to be the class of the field once again as Lewis Hamilton edged his team-mate Nico Rosberg to top the times in Friday practice for the United States Grand Prix.

The Brit was just three thousandths of a second quicker than Rosberg during the 90 minute session which saw just 18 cars take to Austin’s Circuit of the Americas following the absence of Caterham and Marussia.

Rosberg had set the pace after the first run on the soft compound tyres but in the end Hamilton pipped the German to the top spot with a 1.39.085s effort.

Mercedes dominated the session throughout with Hamilton and Rosberg 1.5s faster than their nearest rival on the medium compound rubber.

The deficit was cut once the field switched to soft tyres but Ferrari’s Fernando Alonso was more than 1.1s adrift of the duo in third.

Red Bull Racing’s Daniel Ricciardo recovered from engine problems in the first session to post the fourth fastest time.

Felipe Massa was fifth quickest for Williams just ahead of Ferrari’s Kimi Raikonnen and Toro Rosso’s Daniil Kvyat.

The McLaren pair of Kevin Magnussen and Jenson Button were eighth and ninth while Nico Huldenberg rounded out the top 10.

Reining world champion Sebastian Vettel, who will start Sunday’s race from the pit lane having undertaken a sixth engine change of the year, was last in practice 2 almost five seconds off the pace.

However, the German did post an improved 1.41.4s time in the earlier session.

New Toro Rosso recruit Max Verstappen made his second official F1 appearance in first practice with the Dutchman completing 32 laps to finish 10th quickest.

The opening practice also saw the FIA trial a new yellow flag speed limit system with the field, which the sport’s governing body hopes to implement in the wake of Jules Bianchi’s accident at the Japanese Grand Prix.

Practice 1 Results

Practice 2 Results