But he admitted afterwards the team had to remind him to use his Kinetic Energy Recovery System at times.
Rosberg said: “Until now it’s been interesting because of the tyres, KERS, the rear wing. It’s just getting the hang of everything and learning how to cope with all the different situations.
“Sometimes it’s very complicated out there because my mind is concentrating on testing something, at the same time, I have someone shouting in my ear ‘You forgot KERS, you forgot KERS’!
“Once you forget it, you’re in a mess. It’s quite confusing sometimes.”
He said it was “very positive” to end the day fastest:
“We still have some problems but we are going in the right direction. We learned a lot today.”
Rosberg explained how difficult it was to keep the new Pirelli tyres alive during a long run: “You have to take it very easy at the beginning to save tyres for the end of the stint.
He admitted it was against his racing instincts to drive slower but said: “To be honest it’s very interesting because you need to be really aware of the situation and then it becomes a challenge to make the best out of it.”
He added: “We have always seen exciting races when the tyres have had a problem with degradation. So it’s probably going to be a good thing and some very exciting races.”
Quotes and additional reporting by Leandra Graves
2011 F1 testing
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