Williams enjoyed a solid start to life with the new FW35 after Pastor Maldonado posted the fifth quickest time on the opening day of testing in Barcelona.

The Venezuelan was given the honour of debuting the car following its launch earlier in the day, completing a solid 86 laps and ending up just over a second off the pace set by the Mercedes of Nico Rosberg.

Speaking afterwards, Maldonado insisted that his early impressions of the car were positive, with the team having a 'good starting point' on which to build.

"It was a good day today," he said. "I felt happy after the first run this morning and we then completed a busy day of testing. It was great to get out on track in the new car. The FW35 feels like we have made a real step forward. There is still a lot to discover with the new car, but this is a good starting point for us for the season."

Technical director Mike Coughlan was also pleased with the initial running, despite a minor technical issue when he suffered a water leak.

"It was a very good day for us, with Pastor completing 86 laps, the second-highest of any team today," he said. "Pastor was very comfortable in the car which was shown by his early lap times. We had a small water leak this afternoon on a development part, but we were able to fix it quickly to complete our tyre programme. We feel confident in the core reliability of the FW35 and look forward to continuing with Valtteri tomorrow."