Sergio Perez pleased with new Sauber's potential

After completing his two days of running at Jerez in Spain this week, the Mexican thinks that a good early impression - allied to not being hindered by blown diffuser development like last year - bodes well for the campaign ahead.

"So far it has been a positive two days," said Perez. "Of course we had problems and we could not manage to complete our programme, but still I am quite happy with how it went. I think we are going in the right direction to keep improving."

Sauber has been experimenting with heavily revised rear bodywork over the Jerez week - which includes a more streamlined rear sidepod profile and channels for the exhaust.

"We changed some aero parts, which was always planned after we were going to do the roll out," added Perez. "All in all, I think there is big potential with this car. I think that we can make it better and that is our aim."

Perez does think, however, that the unique circuit characteristics of Jerez - allied to the changeable track temperature - has made it difficult to read too much into lap times.

"Here in Jerez when you miss the window and you don't try the three compounds at the same time then it is difficult. If you try one in the morning and one in the afternoon then it can be completely different - and it changes with the temperature big time."