Pirelli now suspects that Paul di Resta's tyre failure in practice for the Spanish Grand Prix was caused by a cut in the rubber.
After overnight inspection of the remains of the left rear tyre that gave way on di Resta's car, Pirelli suspects that the tread overheated after debris caused a small cut in it.
The overheating, allied to the force being put through the rubber, caused the tyre to fail as di Resta exited the high-speed final corner at the Circuit de Catalunya.
With the failure following three other debris-induced incidents at the Bahrain Grand Prix, Pirelli motorsport director Paul Hembery admitted his company was evaluating whether structural changes were now needed.
"When the tread comes off and exposes the belt underneath, it doesn't look very good - so we need to see if something needs to be changed," he told AUTOSPORT.
"But we also need to consider whether changing something could have an impact on the teams, and whether or not we could have the necessary testing for the new products."