Sebastian Vettel felt that drivers were “on the limit” with their Formula 1 tyres during practice for the Mexican Grand Prix on Friday after a mixed session produced some surprising results.

Red Bull managed to surge over one second clear of the pack in FP2 at the Autodromo Hermanos Rodriguez, led by Max Verstappen, with Renault’s Carlos Sainz Jr. emerging as the closest challenger at the front of the pack.

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Vettel was left to settle for P4 for Ferrari, one-thousandth of a second down on Sainz, before summing up his day as being “slippery” in “very” difficult conditions.

Teams are forced to run maximum downforce on their cars due to the high altitude in Mexico City, but even in doing so end up with less actual downforce than at Monza.

“I think it’s the track with the least sensitivity on power. But I think it’s sort of expected that Red Bull is very strong,” Vettel said.

“I don’t think we had a tidy lap, so we should have been in front of the Renaults.

“Everybody’s on the limit with tyres, trying to get them to work in order to slide less, with the exception maybe of the Red Bull.”

Ferrari teammate Kimi Raikkonen added: We have limited grip on this track, so it’s easy to make a mistake. I got a flat spot, there was a lot

of vibrations and I could do only one lap. It was far from ideal but the car was getting better."

Tyre wear was a particular issue for drivers throughout FP2, with many experiencing significant drop-offs in pace just a few laps into a stint on the Hypersoft tyres.

As a result, it seems likely that drivers many will bid to get through Q2 on the Ultrasoft compound on Saturday to ensure they avoid using Hypersofts at the start of the race.

Vettel heads into this weekend’s race trailing Lewis Hamilton by 70 points in the drivers’ championship, requiring victory to keep the title race alive for another weekend.