George Russell completed a Mercedes practice clean sweep at the Las Vegas Grand Prix after a late red flag truncated the final qualifying preparations in FP3.

The frontrunners — bar Russell — had each completed one flying lap on fresh soft tire as the circuit began to grip up when Lance Stroll’s Aston Martin switched itself off exiting Turn 12, at the north end of Las Vegas Boulevard.

The Canadian parked by a gap in the fence, but the car’s warning lights suggested the hybrid system hadn’t been safely disabled and the car was therefore unsafe for the marshals to touch, necessitating a red flag to recover the stricken car from the track.