Nico Rosberg took back the advantage during second practice for the United States Grand Prix, as the Mercedes driver topped the timing screens with a 1m37.552s lap.
Having finished second to team-mate Lewis Hamilton during the opening session, Rosberg found his rhythm during his supersoft run in FP2 to go three-tenths up on Hamilton, with the pair split by Red Bull's Daniel Ricciardo.
The Australian finished up second, just two-tenths down on the quickest Mercedes.
Hamilton meanwhile made a small mistake on his quick lap, which cost him at least a couple of tenths.
Ferrari's Sebastian Vettel was fourth ahead of the second Red Bull of Max Verstappen – the pair between eight and nine tenths off the pace.
Sixth and seventh went to Force India's Nico Hulkenberg and Sergio Perez, with the pair looking handy this weekend for a decent points haul against championship rival Williams which looks to be struggling for pace in 14th and 16th.
The session saw a brief red flag for debris, which was swiftly collected and the session resumed.
A number of drivers span including Daniil Kvyat, Esteban Ocon and Jolyon Palmer.
