Perez 'very confident' after positive opening day in Bahrain

The Mexican, who came close to winning the Malaysian GP for Sauber, and led in China last weekend, declared himself delighted with his free practice sessions in Sakhir on Friday.

"To me this was a very positive day," said Perez. "I am happy about having had a good Friday and I am very satisfied with the work we have done.

"We have learnt a lot and we managed the tyre degradation on the rear, which everybody has problems with, quite well. We still need to sort out a few set-up issues for qualifying, but I am very confident for tomorrow."

Perez's team-mate Kamui Kobayashi, who started the Shanghai race from the second row of the grid, was less happy with his preparations for this weekend: "Technically we had no incidents but we are struggling on tyre temperatures.

"The lap times on the soft tyres in the short run didn't look too bad, but for qualifying there is still some work to do. Even more improvement is necessary for the long runs and for me this goes for both tyre compounds, soft and medium."