Sergio Perez's Formula 1 victory in the Singapore Grand Prix is under threat as the Red Bull driver faces a stewards' investigation.
The Mexican, who led throughout the timed race at Marina Bay claimed victory by 6.1 seconds from Charles Leclerc, but the win, his second of the season, is in doubt after an incident behind the Safety Car.
The official FIA summons state that Perez fell more than 10 car lengths behind the Safety Car, with the stewards deciding that they would need to speak with Perez before issuing any penalty.
He will report to the stewards at 23:55 local time (16:55pm BST.)
Should he be given a five-second time penalty, Perez would retain the win, fourth of his F1 career.
He finished 15.3 seconds clear of Carlos Sainz, as teammate Max Verstappen was seventh in an attritional race at Marina Bay.
Verstappen did not win the World Championship, which goes to the next race in Japan.
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