The heat is on for the season's finale - and so far it doesn't really suit the Sauber F1 Team. The first day of preparation for the Brazilian Grand Prix on the famous Interlagos circuit was technically trouble free, but both drivers struggled with the high track temperatures as they affected the tyres a lot. Kamui Kobayashi came 12th and 15th respectively in the two free practice sessions. Sergio Perez was 13th and 14th on the time sheets.

Kamui Kobayashi: "We did a lot of set up work today and also tested some aerodynamic items. We had a busy day, but performance wise we are not good yet. Because of the high track temperatures the rear tyres overheated. The lap times were slower in the afternoon than in the morning. The rear is really weak and so far I don't know how to cool the tyres. We will now work on that."

Sergio Perez: "It was a good day in terms of getting done everything that was on the programme. We did a fair amount of work, but the heat just doesn't suit us. I found the car very difficult to drive this afternoon and I think some big changes are required. The difference between the two tyre compounds is really marginal. Let's see how we can improve."

Giampaolo Dall'Ara, Head of Track Engineering: "With regard to today's programme, everything went well including the evaluation of Pirelli's tyres for next year. That was important for the 2013 car design. With regard to this weekend, we will have a long night ahead of us as we are struggling with the grip, but we have collected a lot of data regarding down force levels and set up. Now we just have to put it all together to understand where we can find performance and hopefully to be where we want to be tomorrow."

Check out our Friday gallery, here.