George Russell led Kimi Antonelli to a Mercedes one-two in the only practice session at the Chinese Grand Prix before the sprint weekend starts to unfold.
Russell was more than 0.7 seconds clear of the first driver not in a Mercedes, McLaren’s Oscar Piastri.
Over one lap, that is an almost exact repeat of the advantage Mercedes showed in the season-opening race in Australia last weekend.
Antonelli was 0.120secs behind Russell, while Piastri’s margin was 0.736secs, with Ferrari’s Charles Leclerc and McLaren’s Lando Norris close behind.
Ferrari’s Lewis Hamilton was sixth fastest, 1.388secs off the pace, but his time was set earlier in the session on older tyres after an early spin wrecked his set of medium tyres.
Ferrari were using the innovative rear wing with a flap that opens for the straight-line mode by revolving on its axis by more than 180 degrees, rather than a gap opening by the front of the flat being lifted.
Red Bull’s Max Verstappen was down in eighth place, a massive 1.8secs off the Mercedes pace, and behind the Haas of Briton Oliver Bearman.
British rookie Arvid Lindblad managed only six laps before his Racing Bulls car stopped after a reliability problem on the long back straight, smoke pouring out of the engine airbox before he pulled off at the hairpin.
Sprint qualifying takes place at 07:30 UK time.