After aborting his first flying lap in Q2, McLaren's Fernando Alonso drove slowly back to the pits with an engine failure.
The Spanish driver is anticipating a difficult race as his Honda unit will require a replacement and settings he will not be able to try before joining the grid in 15th position.
"It's a shame. The lap was going well," Alonso said.
"I had improved half a second over the Q1 lap so I think we could have been 13th, 14th, 12th, depending on the others.
"But going into the final corner the engine broke down and I joined the pitlane slowly.
"It was already [going to be] a hard race, but this makes it even harder.
"We have to change the power unit and without the chance to calibrate the engine a bit we will probably not run the race with all the power available, which is already little."
Including today's failure, Alonso is on his second power unit out of the authorised season total of four before grid penalties kick in.
The man who will be racing at Indianapolis next month admits that enduring a failure in qualifying is the worst possible scenario.
"In qualifying it's never easy because you don't have the chance to put a new engine and do a few laps to set it up a bit," he said.
"So in that sense, a bad moment, but we don't choose it.
"I wish we never had that and we changed the engine with its time because of the mileage and not because they break down."
GALLERY: All the pictures from Saturday in Bahrain
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