Ferrari's Kimi Raikkonen made the most of a drying track to record the fastest time of the day before teams halted running for lunch.
The morning was dedicated to wet weather running, with teams sampling Pirelli's intermediates and full wets.
Haas' Romain Grosjean was second fastest late in the session, having put on a set of the SuperSoft compound to set his time which was just 0.43s off Raikkonen's best.
Stoffel Vandoorne just edged out Max Verstappen, also registering a late lap with his UNtraSoft-shod McLaren.
Lewis Hamilton was scheduled to run on the damp track in the morning but an electronic issue kept the Brit's W08 in the garage. Team mate Valtteri Bottas was sent out at the end of the session, achieving nine laps at a slow pace.
Unfortunately, Williams was missing from the session following damage to its Fw40 chassis sustained when Lance Stroll hit the barriers yesterday.
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