Rosberg expects tyres to have an impact

Nico Rosberg believes Mercedes will have benefited from testing their old car in Jerez, as they now have a direct comparison between the 2011 Pirelli tyres and the new 2012 Pirelli tyres.

While the other top teams concentrated on the set-ups and collecting data from running their new 2012 cars for the first time, Mercedes ran the first test session of the new year with last years car.

They opted to do this to give themselves longer to develop their new 2012 car in the factory, which they believe will give them an advantage.

This of course didn't work for McLaren last season as they also missed the first session with their new car and spent the rest of the winter playing catch-up.

But one benefit the Mercedes team will have had is they will have been able to use the new Pirelli compound tyres over the last few days and will then be able to compare the data between how these new tyres react, to how the old tyres used too while on the same machine.

The new tyres have been designed to be 'squarer' which will improve grip and handling for the drivers, while tweaks to the construction of the tyre will mean that plenty of teams will be working hard to work out the optimum tyre strategy over the course of the race weekend.

One of the main reasons behind this will be down to the smaller gap in performance between the compounds.

During 2011 some of the tyre compounds offered around 1.5 seconds per lap difference, but Pirelli have shortened the gap to less than a second per lap between compounds.

'It is going to have a big impact on the racing because the compounds are closer now, It is difficult for me to foresee how that will go, but it will be different. Mercedes driver Nico Rosberg told Autosport Magazine.

'[the compounds] are much closer together now. Degradation is still a big issue and the rear tyre seems a bit strong. Overall, Pirelli has done a good job.'

'It's important to understand the tyres properly because there are some quite big differences to last year,'

'It's a good thing because now we know exactly what the car does [on the new tyres]. We will have a direct comparison when we put the new tyres on the new car.'