Mercedes driver Kimi Antonelli wrecked his car in a heavy crash while teammate George Russell topped the timesheets in the final free practice session before qualifying for the Australian Grand Prix on Saturday.
Antonelli locked up at turn two at Albert Park and skidded hard into a barrier late in the session, leaving a front wheel bouncing away from the crash and team boss Toto Wolff wincing in the team garage.
The 19-year-old Italian said "I'm OK" over the team radio as a red flag halted the session.
The session resumed for the last few minutes, allowing Russell to post the fastest lap of one minute, 19.053 seconds, 0.616 seconds ahead of Ferrari's Lewis Hamilton and third-placed Charles Leclerc.
Russell's time improved upon McLaren driver Oscar Piastri's 1:19.729 in the second free practice on Friday.
Home racer Piastri posted the fourth quickest lap, a full second behind Russell.
The session had already been delayed 20 minutes due to a crash in the preceding Formula 3 sprint race and was halted for eight minutes midway through due to another red flag when Carlos Sainz's Williams car stopped at the entrance to the pit lane.
Teams used the final hour of practice to fine-tune setups and gather data ahead of the season's first qualifying session under Formula One's sweeping new power unit regulations.
Drivers have been grappling with the sport’s new hybrid engines, which place far greater emphasis on electrical energy deployment and regeneration than in the previous era.
Four-time world champion Max Verstappen was sixth quickest, one behind his Red Bull teammate Izack Hadjar.
Racing Bulls rookie Arvid Lindblad, the youngest British driver to start a Formula One season, was 11th.
Aston Martin's Fernando Alonso managed 20 laps for the troubled F1 outfit, whose drivers are on limited run-times due to the threat of nerve damage from vibrations in the car.
His teammate Lance Stroll did not make it out of the garage.
Alonso was 18th quickest, ahead of new team Cadillac's Valtteri Bottas and Sergio Perez.