Pirelli have confirmed Sebastian Vettel's tyre failure during Sunday's Austrian Grand Prix was caused by debris on the track.
The four-time Formula One world champion crashed down the main straight while leading the race around the Red Bull Ring in Spielberg.
Vettel was out in front after stretching his run on the supersoft tyres, leading to suggestions the failure on the Ferrari was caused by fatigue.
However, Pirelli believe the damage was caused after Vettel ran over debris somewhere around the circuit.
"Analysis of the tyre issue that affected Sebastian Vettel at the recent Austrian Grand Prix has been concluded and the results shared with Ferrari," Pirelli said in a statement.
"The few remaining parts of the tyre in question, together with an in-depth comparison to other tyres used in the race, reveal no signs of fatigue or structural failure in the right-rear tyre itself.
"Consequently, the issue appears to be caused by an item of debris, which led to the breakage of the tyre."
Lewis Hamilton went on to claim victory in Austria despite a last-lap collision caused by Mercedes team-mate Nico Rosberg, which saw the German miss out on the podium.