Paul di Resta has admitted he should have driven faster before being forced to retire from the race due to an oil leak.
With zero experience of driving the FW40, the Williams reserve driver had to cover for an ill Felipe Massa ahead of qualifying on Saturday.
The Scot lined up P19 on the grid, but was the backmarker for much of the afternoon as he struggled for race pace.
Di Resta then had to retire the car with 10 laps to go as an issue was discovered with his car.
"I've got a sore shoulder but that's about it," Di Resta told Sky Sports F1.
"That's to be expected after your first time in a car. It wasn't quite as bad as I thought…maybe I should have driven a bit faster.
"I hadn't done a start until half an hour before the race and I dumped the clutch too much. You've got to get it into a certain window. In the end I was very cautious anyway as your spatial awareness of these cars and how wide they are is very hard."
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Di Resta was cautious due to his lack of experience with the new cars, but believes he was unlucky to get lapped just before he made his pit stop.
He added: "I just wanted to make sure I got through the first lap and used every moment I had in that car to my best. We were slightly unfortunate before the pit stop that I got lapped.
"It very much comes down to being around 19 different guys all fighting for the same bit of road, I didn't know what to expect.
"I haven't driven a car with that much downforce for such a long time that you get that much wake off it so you find yourself locking wheels. I didn't want to get too caught up with that.
"I'd have much rather got to the end of the race but we had a small oil leak and as it was a fresh engine for the weekend they didn't want to be taking up engine penalties just because of that."
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