Lewis Hamilton's pre-season preparations hit another bump in the road after the world champion spun on the second day of testing.
Hamilton's Mercedes team missed the majority of Friday's morning session in Bahrain following a gearbox failure.
And, after team principal Toto Wolff said the sport's all-conquering team could ill-afford any further setbacks, Hamilton lost further valuable time after he beached his Mercedes in the gravel.
Hamilton lost control of his car through the right-handed Turn 13 and spun into the sand. Hamilton's accident saw the session stopped as his Mercedes was taken back to the garage on a truck.
The 36-year-old, who is this season bidding to win an unprecedented eighth world championship, later returned to the circuit to complete 58 laps.
But Hamilton finished only eighth of the 10 runners, 1.184 seconds off the pace.
Valtteri Bottas will take over driving duties for Mercedes following the one-hour lunch break, with Hamilton back in the car on Sunday afternoon.
It will be Hamilton's final running before he opens the defence of his title in the Gulf Kingdom on March 28.
Daniel Ricciardo continued McLaren's encouraging pre-season form by heading the time charts.
The Australian finished 0.124 sec ahead of the returning Fernando Alonso.
Alonso is back on the grid following a two-year hiatus and his running in Bahrain was his first in a Formula One car since he suffered a fractured jaw in a road cycling accident last month.
But the double world champion, 39, showed few signs of rustiness as he completed a solid 59 laps for his Alpine team.
Red Bull newcomer Sergio Perez finished third, while there was trouble for Aston Martin as a gearbox failure restricted four-time world champion Sebastian Vettel to only nine laps.
"Unfortunately we did not have a productive morning," said Vettel, who has joined the British team after he was dropped by Ferrari.
"We had an issue with the gearbox and we had to change it and that cost us quite a bit of time.
"We did not get many laps in so this morning was not great, in terms of track time, but it is a long year and a long season ahead of us. It is crucial to settle in quickly but eventually we will all improve with more time on the track."
