The cause of Sebastian Vettel's tyre failure during the Abu Dhabi Grand Prix remains unknown after Pirelli ruled out a structural damage.
Vettel started in pole position at the Yas Marina Circuit on Sunday but his race lasted just two corners after a right-rear problem sent him spinning off the track. Although he made it back to the pits, the damage to his rear suspension was too severe and he was forced to retire.
Pirelli and Red Bull immediately launched an investigation after the race, but the Italian manufacturer revealed on Wednesday that a detailed examination of the rubber has shown that there was no structural failure and also doubts that debris is to blame.
"We can confirm a structural failure was not the cause of Sebastian's deflation in Abu Dhabi," Pirelli motorsport director Paul Hembery said.
"It is a conclusion we have arrived at together with Red Bull Racing following a detailed examination and analysis of the remains of the tyre.
"We cannot rule out debris on the track causing damage to the tyre, which then provoked a deflation, but having looked at the track closely there is no direct evidence of this."