Reigning world champion Sebastian Vettel set the fastest time during the morning session on Day 2 at the Circuit de Catalunya.
Vettel's time of 1:22.197s was just over half a second quicker than the fastest time set by Lewis Hamilton in his Mercedes W04. The Brit completed the most laps, 64, almost a full race distance.
The German's quickest time was set on the soft compound tyre.
It was a disappointing morning for Lotus and Kimi Raikkonen as a gearbox change restricted the Finn to just four laps, none of them timed.
Valtteri Bottas sampled the Williams FW35 for the first time, completing 53 laps in his new car.
The morning session passed without any stoppages.