Mercedes car just needs "tuning" - Wolff

Although Mercedes has won in China and Russia so far, it knows that Ferrari has a car that is better on tyres and can operate in a wider temperature window with F1's new rubber.

But Mercedes motorsport boss Toto Wolff thinks that Mercedes' problems can be readily solved – with sources suggesting key areas of focus will be suspension and weight reduction in a bid to improve the car's balance.

Ahead of a Spanish Grand Prix where Pirelli's harder tyres, which Mercedes has not liked too much, will be run, Wolff thinks that there is no reason to be too worried.

"I don't think there is a particular pattern," he said. "It is very marginal with tyre compounds, interaction with the track, the surface of the track, and the track temperature itself. Then there is surface bulk, and carcass temperatures.

"There is so much interaction you just have to get right in order to be in the window. One thing is for sure: we have a very fast race car, a fast qualifying car.

"We just need to tune it. And this is an exciting exercise."

Close battle

Wolff thinks it impossible to choose if Mercedes or Ferrari have the best car at the moment – which is why his outfit needs to push hard to get ahead.

"It is going to be very close – in fact more than very close," explained Wolff about his thoughts on the title battle. "They [Ferrari] came out of the winter with a good car and it seems to suit Sebastian [Vettel] a lot.

"We just need to stretch ourselves to perform as good as we can and, if we do like we did with Valtteri [in Russia], we are able to compete."