WILLIAMS are in a positive mood after a cautious start to Formula 1 testing in Spain.

The Grove-based outfit put their new FW41 through its paces on a filming day in Barcelona at the weekend.

And on Monday, they joined the rest of the paddock for the first official test of the season at the Circuit de Barcelona-Catalunya.

Lance Stroll was behind the wheel for the morning session, completing 46 laps when he was ninth-fastest overall.

Sergey Sirotkin took over the driving duties in the afternoon, but the inclement weather hampered his progress as he was bottom of the time sheets after only logging 28 laps.

Williams’ chief technical officer Paddy Lowe was pleased with the opening sessions.

He said: “Overall it was a good day.

“We had a bit of a cautious start as, despite having a filming day, we still had many parts of the car that we wanted to monitor.

“Lance got going properly around 11am, so had a couple of hours proper running before lunch and completed a total of 46 laps.

“We weren’t pushing too hard as it was more about systems checks, but we are relatively happy with the car.

“Sergey took over driving duties for the afternoon.

“We did a number of aerodynamics tests in the early part of the session, but by time he was going out for proper runs we had lost track conditions as the temperatures plummeted.”

Stroll added: “So far, so good.

“It’s a new car, which means there are lots of things that have to be done to get on top of it, so it’s good we had no problems.”