Lotterer overturned Edoardo Mortara's hold of the session with a lap set after the chequered flag had flown on the second free practice session, putting his Porsche on top prior to his and the team's home event.
The Mercedes duo of Stoffel Vandoorne and Nyck de Vries set the first timed laps of the second practice session, but the times quickly tumbled into the pace from the earlier session - Alexander Sims (Mahindra) first to break into the 1m06s in FP2, swiftly followed into that bracket by DS Techeetah's Antonio Felix da Costa.
