Tyre pressures could cause 'unpredictable' Japanese GP

In a bid to guarantee safety, Pirelli has imposed a minimum pressure of 21.5 PSI for the front tyres and 20.5 PSI for the rear tyres at Suzuka.

Those levels are higher than some teams would ideally like, and are set to make life difficult in the race, with them prompting a potential lack of grip and causing the tyres to overheat.

When asked by Motorsport.com about the implications of the high pressures, Red Bull's Daniel Ricciardo said: "I think that is going to be the biggest challenge for everyone, tyre temperatures.

"Probably not so much wear, but keeping temp down in the tyres.

"It is not just an easy thing to do. Especially around here, you have so many corners one after the others. You can only keep them so low."

Pirelli boss Paul Hembery denied the pressures were too high.

"They are quite correct based on the data we've been given from the cars," he said. "Unfortunately that's based on a combination of the most extreme performance levels, so there's a big gap between the frontrunners and the people who are a little bit behind.

"The cars haven't stood still, there's been a dramatic increase in performance, and a dramatic increased in loads.

"So that's necessitated some changes. Suzuka is one of the most severe tracks of the season so it would be quite normal for us to be taking that approach."

Alonso wary

Fernando Alonso reckoned that the limits contributed to a number of drivers running off during final practice, and may cause incidents in the race.

"Definitely there is a little bit lack of grip, and a big drop off, even more than normal, due to the pressures," he said.

"The cars here are moving around more and we saw in FP3 some mistakes from all of us, going wide on some corners.

"Definitely there is less grip out there, but if the limitations are these ones and the tyres are safe to race, it is welcome."

His McLaren teammate Jenson Button added: "It's going be tough for everyone, the race, because the pressures are so high, the tyres are overheating after one lap.

"So everyone will have troubles tomorrow, us included."