Nico Rosberg says Mercedes cannot afford to rest on its laurels and will keep innovating to prevent rival teams 'copying' it.

Though it has dominated the sport for the last two years, Mercedes has described the W07 as another step forward in terms of development, with Rosberg insisting it is being forced to keep inventing so as to fend off rival replications.

Driving the W07 on the morning of the third day before handing over to Lewis Hamilton in the afternoon, Rosberg amassed another 74 laps and was impressed with the latest updates on the car.

"We need to invent stuff to stay ahead because everybody else is going to copy us all the time, so if we want to be better we have to keep inventing and keep one step ahead.

"That is what we managed to do with the floor, for example. It is really futuristic, really cool to see, and it shows the quality of the team."

Mercedes split Rosberg and Hamilton on day three so as to give the drivers a break following an intensive set of mileage over the last two days. In three days, the team has now completed the equivalent of six race distances.