Sergio Perez admitted to being surprised by the level of tyre wear he experienced on the second day of testing at Catalunya, despite ending the day with the fastest time.
The Mexican set the fastest time of the week to lead the way on Wednesday, setting his benchmark time on a short run on the soft Pirelli tyre.
Speaking to reporters afterwards however, the McLaren driver admitted he was surprised by the degradation of the tyres when carrying out longer runs on track – stating that the tyre wear had been more extreme that seen in the past.
"It's extreme,” he was quoted by Sky Sports
. “It's very, very difficult the degradation - it's a big surprise. "Normally we see in winter testing a lot of degradation, but never this much.
“We are going to have sometimes cold races like here, so it's a bit of a worry, but we are still learning about the tyres and once we go racing I hope things can change with the tyres."
Perez, who is known for being softer on his tyres than many of his rivals, admitted there was little he could do to prevent the degradation, which in turn was making it difficult to learn about his new car.
"As a driver obviously you can help the tyres to last a bit longer, but at the moment we are learning from the tyre is basically very weak and there's very little the driver can do now to help the degradation," he said. "The tyre is difficult to do two or three laps with it. Once you do a lap you are starting to fight degradation so it's pretty difficult to learn anything from your car or from the balance.
"[However] I think the car is definitely competitive. We have no idea how the others are, the car has a good base but this base has to be improved for the first race. The team is working very hard to find more and it has to be our approach. I think we have to find quite a bit more downforce for the first race.
"I think the car in general is quite strong, it has a very good base and a very good potential to be improved if we can make them work. It's very difficult to tell you that the high-speed is bad for us, or the low-speed [for example]. I think in general we have to improve our car."