Ayumu Iwasa ended a frantic Free Practice session fastest of all as the DAMS man set a 1:22.081 to lead the way. The Japanese driver got his best lap in just prior to the third Red Flag of an incident-filled session.
Victor Martins was next best for ART Grand Prix, while Richard Verschoor ended up third for Van Amersfoort Racing but found himself in the barriers in the closing minutes.
Following installation laps, Frederik Vesti set the initial pace with a 1:26.529 for PREMA Racing. The first Red Flag came early after contact at the final corner between Ralph Boschung and Roman Stanek.
With both cars recovered, Practice resumed with 31 minutes remaining of the session and both PREMAs carried on from where they left off. Vesti lowered his best to a 1:26.164, just over a tenth quicker than teammate Oliver Bearman in P2 as the track continued to improve. Dennis Hauger moved up to P1 with a 1:23.692 before Jack Doohan took over the top spot, setting a 1:23.616.
The second Red Flag of the session came with just over 20 minutes remaining after Bearman lost the rear of his PREMA at Turn 8 and nosed into the barriers. Back to green with 18 minutes to go, plenty switched to the supersofts tyres to get a feel ahead of Qualifying on Friday.
Hauger moved himself back to the top of the times on a 1:23.139 before Victor Martins and then Doohan pipped him once more. The Australian lowered his best effort to a 1:22.752 to lead the way with under 10 minutes to go.
The MP Motorsport driver reclaimed P1 on his next lap as the top spot continued to trade hands. Martins moved back into first just as Iwasa closed the gap to the Frenchman to 0.012s in his DAMS. Martins’ next effort was even better, taking his benchmark down to a 1:22.127.
Iwasa finally got to the top on a 1:22.081 just before Verschoor brought out the third and final Red Flag of the session. The VAR driver hit the barriers at the same point as Bearman after an identical moment of oversteer, ending the session early with just over a minute remaining on the clock.
Split Qualifying begins at 15:10 local time with Group A followed by Group B at 15:34 on Friday in Monte Carlo.