The blow-outs suffered by Max Verstappen and Lance Stroll in Baku gave everyone involved serious cause for concern. At the time of writing Pirelli was still conducting an investigation into what the cause may have been, but both failures were on the left-rear and on the pit straight where the cars are reaching 200mph and beyond. Both were of the hard compound. At the time of the failure, Stroll’s had completed 30 laps from a fully fuelled-up start. Verstappen’s had covered 34 laps from being fitted on lap 12 (when the fuel load would have been around 25kg lighter than at the start of Stroll’s stint). Both failures appeared to be on the inside shoulder of the tyre.
Sebastian Vettel – who has suffered from Pirelli tyre failures approaching Eau Rouge in 2015 and on the pit straight in Austria 2016 – was unimpressed. “I think both of them, Lance and Max, got really lucky today. If this happens at pit entry, we’re looking at a different incident. I think we got lucky with both incidents. But that mustn’t happen, absolute no-go.”
Pirelli suspected a possible cut from carbon fibre debris and cited as supporting evidence a large cut to the tread of Lewis Hamilton’s left-rear found after the race.