Sep.11 (GMM/ A new theory about what caused the tyre blowouts at Spa-Francorchamps recently has emerged.

Pirelli was on the back foot after the Belgian grand prix weekend, as it analysed what caused the tyre explosions suffered at high speed by Nico Rosberg and Sebastian Vettel.

F1’s official supplier came under attack for the quality of the construction of its tyres, but insisted that track debris and excessive wear were actually the causes.

Nonetheless, tyre pressures were mandatorily raised for the subsequent Monza race, triggering the post-race stewards enquiry about Lewis Hamilton’s win.

Romain Grosjean, who had followed Vettel for several laps before the Ferrari driver’s incident at Spa, said he never believed the track debris theory.

“Seb didn’t go off the track even once,” said the Frenchman.

However, Germany’s Auto Motor und Sport has published a new theory, based on a photo that has emerged of a sharp, damaged and raised section of kerb at Eau Rouge.