Hulkenberg ended more than 2.5s clear of the rest of the field, having set a 1m 23.110s in the late afternoon. Only Sebastian Vettel has gone faster so far in 2016, and the Ferrari driver set that benchmark on Pirelli’s new ultrasoft tyre.
“Today we tried a bit more [than the competition] to test where our package stands at the moment,” Hulkenberg explained. “There is no reason to get over excited.
“It looks okay so far, but there is still a lot of work to do. We are not at our best: there is still stuff to learn and look at.
“We’re on schedule, on target - we're learning more and more every day. Days like this are very encouraging, but I wouldn’t get too excited in these early stage to be honest.”
Chief race engineer Tom McCullough said the team had made several positive steps despite some minor glitches, adding: “Nico’s first day of winter testing saw a continuation of data gathering to help with our understanding of the VJM09, as well as further car sign-off tests.
“The afternoon allowed a chance for Nico and his engineers to carry on with set-up adjustments and we made some good progress as the day unfolded.
“We had a few small ‘new car’ problems that required attention in the garage and ultimately cost us some track, but we still ended the day just shy of 100 laps.”