Mercedes have been forced into making an unscheduled engine change ahead of qualifying for the Saudi Arabian Grand Prix, after a problem was spotted with Valtteri Bottas' power unit during final practice.
Due to the lack of time for investigations between third practice and qualifying, Mercedes have slotted in a previously used power unit from Bottas' pool.
It means that Bottas will not be hit with a grid penalty for this weekend's race.
"We had a fuel leak on Bottas' PU at the end of FP3," read a short statement from Mercedes.
"Without sufficient time to diagnose and resolve, we are swapping it for a unit from the pool."
Bottas finished third practice in sixth place, seven-tenths away from teammate Lewis Hamilton in second. Hamilton is running a much fresher and so-called "spicy engine" that was introduced at the Brazilian Grand Prix.
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