Chasing the Mercedes hard were the Ferraris of Sebastian Vettel and Kimi Raikkonen, split by the Red Bull of Daniel Ricciardo, whose team mate Daniil Kvyat was sixth.
Williams’ Valtteri Bottas, Toro Rosso’s Max Verstappen, Force India’s Nico Hulkenberg, and Lotus’s Pastor Maldonado completed the top ten in a session in which everyone was exploring the limits of adhesion. Raikkonen in particular had a lurid spin at Turn 4 after locking up into the corner.
Hamilton and Rosberg dominated from the get-go as the predicted thunderstorms failed to materialise and the weather was as pleasant as the new team buildings in a paddock that nevertheless manages to retain its old patina. Hamilton posted 1m 14.451s, Rosberg 1m 14.472s. It wasn’t all plain sailing, however. The Englishman complained of a clutch vibration, the German of understeer.
With 35 minutes remaining Vettel moved ahead for Ferrari with 1m 14.223s, which he subsequently trimmed down to 1m 14.168s, before Rosberg went back ahead with 1m 14.090s. Hamilton’s reply was 1m 13.543s, the sole sub-1m 14s time, and that left Rosberg to whittle his time to 1m 14.087s and then 1m 14.062s.
Ricciardo’s smile was broader than usual after he managed 1m 14.449s in the Red Bull equipped with the latest specification Renault engine, though he will carry a 10-place grid penalty into Sunday's race as a result of the change. That compared with team mate Kvyat’s sixth fastest best of 1m 14.696s with the older spec powertrain, bearing out Renault’s expectations of the newer version being worth a couple of tenths.
Raikkonen was late out but soon got down to some respectable times before going off on his grass-cutting excursion at Turn 4 which left him fifth on 1m 14.549s.
Bottas had a much better morning than Williams team mate and local hero Felipe Massa; the Finn was seventh on 1m 14.886s, the Brazilian only 17th as he struggled to find a good balance.
Verstappen, who half span at Turn 3 early on, was eighth for Toro Rosso with 1m 14.960s, leaving Hulkenberg and Maldonado to round out the top 10 with 1m 15.174s and 1m 15.192s respectively. The Venezuelan’s team mate for the morning, Jolyon Palmer, was 12th, two-tenths down, and caused 13th fastest Jenson Button a few moments of concern when he was released straight into the McLaren’s path at one stage.