Sebastian Vettel has led calls for an investigation into the apparent tyre failures suffered by Lance Stroll and Max Verstappen during the Formula 1 Azerbaijan Grand Prix.

Both drivers suffered heavy high-speed crashes after their left-rear tyre seemed to give way.

On Lap 30, Stroll was pitched into the wall on drivers’ left as he rounded Turn 19 – effectively a kink in the long front straight.

The Canadian was still running the hard compound Pirelli tyres on which he’d started the race at the time of the incident.

Later, Verstappen crashed out only metres up the road with a seemingly identical problem.

Indeed, it prompted Red Bull’s sporting director Jonathan Wheatley to radio FIA race director Michael Masi to advise there was no warning prior to Verstappen’s failure, effectively recommending the race be red flagged on safety grounds.

Verstappen had pitted on Lap 12 to swap his soft tyres for a set of the hard compound rubber, crashing out 32 laps later.

“I saw that he lost the car very late in the straight,” Vettel said of his Aston Martin team-mate Stroll’s crash.

“I thought maybe first he clipped the wall outside of 19. But then I looked the next lap and there was not a scratch.

“That would have been very unusual, but I couldn’t explain why would crash so late in the straight.

“But when Max had the same issue, then it was quite clear that, you know, ‘who is next’ sort of thing.”

Speeds down the more than two-kilometre front straight in Baku easily exceed 300kmh, making it one of – if not the – fastest sections of track all season.

What’s more, as a street circuit, it is hemmed in by walls, offering little opportunity for the driver to react and save the car before careering into a concrete barrier.

“There needs to be a bit of an investigation because it’s probably the worst place of the year you want to have this,” Vettel said.

“It could go massively wrong if you get it wrong, and so close also to pit entry to the wall there.

“We’re doing way over 300[kmh] so, yeah, I was a bit concerned but with a red flag, then I knew that we all fitting different tyres and it should be fine.”

Race winner Perez echoed the thoughts of the four-time world champion.

“I think it’s something that we have to investigate and see because the speeds and getting a failure there is something pretty extreme.

“Luckily, nothing happened today, but it’s something that has to be reviewed and made sure that we understand what’s going on.”

While also keen to understand the cause of both incidents, Pierre Gasly suggested there could be a number of factors at play.

“There will be a couple of explanations,” he said.

“Whether it’s tyres or car related, I think there will be some investigations.

“In terms of safety, you see the both incidents – I think probably Lance, it happens around 270-280[kmh], and for Max over 300 kph.

“At such speed, you don’t want to have this kind of failure.

“I’m really glad both of them came out of the car okay, but more than that, we need to understand exactly what’s happened to make sure it doesn’t happen again in the future.”