Pirelli have suggested that debris was the cause of two tyre failures at Sunday's Azerbaijan Grand Prix, as a full investigation gets underway at the company's headquarters in Milan.
Red Bull's Max Verstappen and Aston Martin's Lance Stroll both suffered high speed crashes after the rear-left tyre failed on both cars. Verstappen lost control of his Red Bull when travelling at speeds in excess of 300km/h.
Both Stroll and Verstappen walked away from their seperate incidents but the young Canadian driver was audibly shaken in his radio message after the crash.
While Verstappen, who hit the wall while in the lead with five laps remaining, was visibly angry and kicked the tyre while leaving the track.
Speaking in an interview after the race, Verstappen was clear in his assessment of the incident.
"I didn't feel anything up until the moment that I suddenly went to the right, the tyre just blew off the rim and it's not a nice impact to have, it's quite a dangerous place to have a tyre blowout at that speed," Verstappen told Dutch TV.
"For sure [there will be talks with Pirelli] but we know the result from that conversation already and that's a bit hard to accept,
"It will be related to debris, it's like that. I'm sure there will be talks, Pirelli isn't happy with what happened here today, but it doesn't change anything to the race and the result I got here."
When asked if debris could have caused the puncture in the tyre, Verstappen remained firm.
"I don't think so, I wasn't stressing the tyres," he said.
"It felt comfortable and I didn't feel any vibrations before it let go.
"[Debris] is difficult. We're doing the same line every lap because everyone wants to be in the slipstream. It's very weird that it happens to me.
"I think they cleaned the track [after Stroll crashed] but Pirelli is probably going to say it was carbon debris on track."
Shortly after the race, it was revealed that seven-time world champion Lewis Hamilton had also suffered a cut on his rear-left tyre. Which was confirmed by Pirelli motorsport director Mario Isola.
"I believe I can exclude that failures were due to tyre wear, because it is not a matter of tyre wear," Isola said.
"We found a cut on the inside shoulder of the rear left tyre used by Hamilton in the same stint.
"The cut was quite deep and big -- probably 6-7 cm -- but not cutting the construction, so the tyre was still in one piece.
"But it seems it is a cut due to debris. It is not a more-stressed tyre and we have evidence of another cut in the same position [on Hamilton's tyre].
"We have other cars with the same number of laps, same tyres, without any issues.
"So the preliminary investigation is that it is probably due to an external factor or debris, kerb, or whatever... the plan now is to make a thorough investigation and make a report to the teams and the FIA"
Pirelli will hope to have an answer for teams before racing continues in France on June 18, where Verstappen will hope to extend his championship lead over rival Hamilton.