Mercedes AMG Petronas
Nico Rosberg heaped praise on his Mercedes team after he racked up 157 laps on the first day of testing at Jerez.
Rosberg, who finished runner-up in last year's championship, set the third fastest time at the Spanish track as he put the W06 Hybrid through its paces.
"That was a great start to the winter testing," he said. "In the beginning it's all about reliability and we managed to do a lot of mileage today.
"The guys in the factories built a complete new car and now we come here and it's working great, so the team did a fantastic job over the winter.
"I was able to do some good long runs on the first day and that's really amazing. We have such a great team and this is what makes me really happy.
"As a driver, you always want to find out how quick you are compared to the others - but that will have to wait until qualifying in Melbourne. The next testing days are all about making sure we know the car inside out and we've made a good start with that today."
