MILAN (AP) Formula One tiremaker Pirelli has concluded that Sebastian Vettel's shredded tire last weekend at the end of the British Grand Prix was caused by a slow puncture.
The Ferrari driver appeared to be heading for third place at Silverstone until his front left tire suddenly blew apart two laps from the finish. The four-time F1 champion managed to steer his Ferrari back to the pits for a tire change, and secured seventh place to cling onto his championship lead.
British driver Lewis Hamilton won the race to cut Vettel's overall lead to one point.
''A full investigation has now confirmed that the original cause of the failure was a slow puncture,'' Italian manufacturer Pirelli said in a statement. ''The consequent driving back to the pits on an underinflated and then flat tire led to the final failure.''
Vettel's Ferrari teammate, Kimi Raikkonen, also experienced a similar tire failure one lap before Vettel in a remarkable finish.
Raikkonen was set for second place but his tire problem allowed Valtteri Bottas to complete a Mercedes one-two with Hamilton. The Finnish driver even looked set to lose his podium spot to Vettel, but in a bizarre twist he ended up third after Vettel's problem occurred.
''Raikkonen's damaged tire shows less evidence of what occurred, so further tests and analysis are still ongoing in Pirelli's laboratories and indoor testing facilities,'' Pirelli said. ''It will take a few more days to reach a definitive conclusion.''
The championship continues at the Hungarian GP next week.