At the final round of the season in Brazil, preparations are already underway for next year, as Pirelli tried out two new compounds during free practice today. The teams had at their disposal two extra sets of a new hard compound tyre for Friday free practice only, which is a bit stiffer than the current medium compound and has a lower working range.

For the race, the drivers have the current P Zero White medium tyre nominated along with a new P Zero Yellow soft compound, which was used at the young driver test in Abu Dhabi last week and during free practice at the German Grand Prix. All the teams tried out both of the new compounds today, in preparation for the final race of the year.

In total, the teams had five sets of tyres available for Friday. All the sets were returned at the end of the day, leaving them with their usual allocation for the rest of the weekend.

During the first free practice session in the morning, where nobody used the soft compound, Red Bull Racing's Mark Webber went quickest with a time of 1:13.811 on the P Zero White medium tyres.

In the afternoon, the teams concentrated on longer runs with full fuel (between 120 and 160 kilograms) using both nominated compounds in order to simulate race conditions. The weather was dry and warm with an ambient temperature of 26 degrees centigrade and track temperature of 41 degrees, although cooler conditions are expected for the race. In the last half hour of free practice most of the drivers ran on the soft compound, with McLaren's Lewis Hamilton going fastest thanks to a time of 1:13.392. The top seven were separated less than four-tenths of a second.

The P Zero Yellow soft tyre is expected to last for up to 25 laps on Sunday with the P Zero White medium tyre lasting for around 35 laps. This means that most drivers should stop two or three times on Sunday. There is around 0.8s seconds per lap difference between the soft and the medium tyres so far, opening up a wide variety of possible strategies. However, rain showers are predicted both tomorrow afternoon as well as for the race on Sunday, which could have a dramatic effect on the action.

Paul Hembery: "This weekend is our last chance to test our new compounds until official testing starts in February, so we intend to make the most of it. We've got some reasonably significant changes planned for next year. The first indications are that we are on course to achieve our objective of decreasing the gap in lap times between the compounds to less than a second but of course there's still plenty more to come. In the coming days we'll be analysing the data and feedback from the drivers as we continue to work towards 2012. Before then, we've got the final grand prix of the year to look forward to, where we'll see the new soft tyre in action on this demanding Interlagos track, which challenges the rear tyres in particular. A lot will depend on the weather of course: Brazil has a habit of producing some very dramatic races and it would be great to finish our first season on a high."

Check out our practice gallery, here.