Ferrari opted to replace its gearbox before the race.
Leclerc was due to start the race from 19th place, ahead of Logan Sargeant of Williams.
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A problem with his Ferrari led to Leclerc’s crash in Q1 – his first flying lap was nearly three-tenths slower than Max Verstappen.
His team-mate Carlos Sainz qualified on the front row, behind only Verstappen.
“I don’t have the answers,” he said after qualifying.
“We will have to check the data. But, above all, check the car.
“Because there was definitely something odd.
“I almost lost it during the red flag when I was at 70 km/h, and there was no warning.”