Fernando Alonso suffered a cut to a tyre which forced him to reduce his running during Friday practice for the Mexican Grand Prix.
The first practice session started in damp conditions with the track drying out enough for slick tyres enough after around half an hour. However, Alonso later went back out on intermediate tyres despite the dry track and he confirmed a cut to his medium tyres had forced the change.
“I had a cut on the tyres, I had a puncture and we could not run more with the dry tyres," Alonso said. "The Friday was OK, we keep making progress and the car keeps on improving with the new parts. Now we need to see what we can do in the race."
And Alonso says McLaren knows qualifying is a write-off due to the engine penalties which both drivers will have to take.
"In the qualifying unfortunately whatever position, we will start last with the penalties, so we will concentrate on the race pace and the tyre management because we saw a lot of degradation [on Friday], it was more than expected so we need to put some action on that.”
Pirelli's Mario Isola says McLaren was advised not to run the tyre after such a deep cut, but found no other team had the same issue.
"It was the only one," Isola said. "Obviously when we saw the cut we started to investigate if there was anything on track which could cause the cut but it was the only one so probably some debris on track or something that was cutting just that one tyre.
"When we see a cut that is reaching the canvas we always tell the team not to use that tyre."
AS IT HAPPENED: Mexican Grand Prix FP2
Eric Silbermann's Mexican grumpy preview
Technical analysis: United States
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