Shanghai - Toro Rosso's Alexander Albon lost control and smashed at high speed towards the end of final practice on Saturday for the Chinese Grand Prix, bringing the session to a premature end.
Mercedes' Valtteri Bottas went fastest for the second practice in a row, with the Ferraris of Sebastian Vettel and Charles Leclerc second and third.
The 23-year-old Albon climbed gingerly out of his wrecked car, but only after a huge scare that drew gasps from the crowd in Shanghai.
The Thai-Briton, who is in his first season in F1, careened into a wall as he entered the straight with less than 10 minutes left of third and final practice.
His car was badly mangled and there was a frantic call from engineers asking if he was okay.
"I'm fine, sorry," came the reply from a shaken Albon, who was able to walk away and was assessed by medical personnel.
He was later given the all-clear but will miss qualifying because his ruined car will not be fixed in time, Toro Rosso said.
Bottas clocked a leading time of one minute 32.830 seconds, 0.392 seconds ahead of Vettel and 0.418 of Leclerc.
World champion Lewis Hamilton was fourth in the other Mercedes.
Before his dramatic late smash, Albon clocked the ninth-quickest time.
Qualifying for the Chinese Grand Prix - the 1 000th race in Formula One - takes place at 2:00 p.m. (0600 GMT).
Chinese Formula One Grand Prix free practice times in Shanghai on Saturday:
1. Valtteri Bottas (FIN) Mercedes 1:32.830, 2. Sebastian Vettel (GER) Ferrari 1:33.222, 3. Charles Leclerc (MON) Ferrari 1:33.248, 4. Lewis Hamilton (GBR) Mercedes 1:33.689, 5. Nico Hulkenberg (GER) Renault 1:33.974, 6. Kimi Raikkonen (FIN) Alfa Romeo Racing 1:34.246, 7. Max Verstappen (NED) Red Bull 1:34.447, 8. Carlos Sainz (ESP) McLaren 1:34.510, 9. Alexander Albon (THA) Toro Rosso 1:34.600, 10. Daniil Kvyat (RUS) Toro Rosso 1:34.783, 11. Lando Norris (GBR) McLaren 1:34.938, 12. Sergio Perez (MEX) Racing Point 1:35.078, 13. Daniel Ricciardo (AUS) Renault 1:35.142, 14. Lance Stroll (CAN) Racing Point 1:35.223, 15. Pierre Gasly (FRA) Red Bull 1:35.326, 16. Antonio Giovinazzi (ITA) Alfa Romeo Racing 1:35.726, 17. Romain Grosjean (FRA) Haas 1:35.771, 18. Kevin Magnussen (DEN) Haas 1:35.998, 19. George Russell (GBR) Williams 1:36.124, 20. Robert Kubica (POL) Williams 1:36.176