Rosberg: A different challenge

Nico Rosberg sees no problem with Pirelli's current range of Formula 1 tyres, just over a week after Mercedes team-mate Michael Schumacher criticised them at the Bahrain Grand Prix.

Speaking after the race at Sakhir, Schumacher hit out at the rate of tyre degradation, which he reckons forces drivers to stay within both their own and the car's limits.

But with Pirelli now in their second year as F1's sole supplier - and having been given the aim of spicing up the racing - Rosberg, in contrast, welcomes the challenge.

"I don't think it is an issue, I think it's good," he told Sky Sports News at the Mugello test, which started on Tuesday. "It's a challenge - it's a different challenge, about tyre management. It's very interesting; it makes the racing fantastic also, a lot of overtaking thanks to that as well."

There has been plenty of overtaking in what has been an ultra-competitive start to the current season, with each of the opening four races producing a different winner.

Tyre management has therefore become more crucial than ever as teams have striven - and struggled - to understand the rubber and get it operating in the right window.

Mercedes, for example, overheated their tyres in Australia before suffering the opposite problem in wet conditions in Malaysia the following week.

There then followed a dominant performance in China, where Rosberg scored his first win having also taken an impressive pole position.

However, Mercedes were unable to follow up their Shanghai result in the Middle East, despite having appeared strong during Friday practice in Bahrain.

Rosberg said he was happy with his first morning in the car at Mugello, despite the wet conditions and a stoppage at Turn 4 that brought out the red flags.

"It was good. We learned some valuable things this morning in the wet. Lately, we haven't been that strong in Malaysia, so that was useful," said the German, who ended the morning fifth fastest overall.

"We even got some dry running in in the end; we did some useful tests there already, so we learned something, which was great, so it was a good start to the test here.

"It's an impressive track. It's very, very fast and fun out there and it's good preparation for Barcelona, for the high-speed corners there."

Rosberg says Mercedes will introduce upgrades ahead of next weekend's Spanish Grand Prix as they seek to place their W03 car at the front of the pack - and keep it there.

"We always have bits and pieces coming for every race, so there's going to be some things in Barcelona too," he said.

"It's an ongoing process and that's one of the areas where we really need to make sure that we're strong this year - and I think we can be strong in that area, which is in-season development. So let's see."

Given the frenetic state of play in F1 at the moment, though, the 26-year-old played down his immediate prospects at the Circuit de Catalunya.

"You never know at the moment. It's all such a mix up from one race to the next. For sure we have a decent car, so I'm sure we can do a good result. But how far up, I don't know," he added.

Rosberg is scheduled to hand over driving duties to Schumacher on Tuesday afternoon before returning to the cockpit for the final day of the test on Thursday.