Paul di Resta impresses after diving into the deep end

A day that had started with the Scot ironing a shirt for his regular television commentary duties veered wildly off course after Williams race driver Felipe Massa fell ill in final practice.

Di Resta, who had not previously driven the latest generation of Formula One cars and whose last grand prix was in 2013 with Force India, was rushed in as reserve.

He had already been informed of the situation the night before but Massa was then cleared to drive on Saturday morning and it looked like the crisis was over. And then the Brazilian felt dizzy again.

"I'm not going to lie, I was scared, nervous, anxious," di Resta told Sky Sports television.

"I've not driven one of these cars for three-and-a-half years, apart from 10 laps I did in a 2014 car, and then you get thrown into qualifying which is the deepest of all deep ends -- it's like jumping off a cliff and seeing how you fight for survival."

In the end, he did much more than might have been expected.

The 31-year-old's time of one minute 19.868 was only seven tenths slower than 18-year-old Canadian rookie team mate Lance Stroll and quicker than Sauber's Marcus Ericsson.

He completed five flying laps and went quicker every time, progressing from an initial 1:22.289.

"Honestly I felt quite comfortable quite quickly. As soon as I let go of the pit limiter it was kind of there and I was improving by half a second a lap. There is still plenty of potential there," he said.

Britain's Damon Hill, the 1996 world champion who also works for Sky, was among those impressed with what he saw.

"It's not quite me leaping in the ring with the heavyweight champion of the world but it's not far off," he said. "It's a huge ask to give a guy no track time and literally half an hour before he's due to go out, put him in the car.

"He didn't make any mistakes, got faster and faster and he's not last. It sounds like faint praise but it's not, it's a superb effort so well done to him."

Williams technical head Paddy Lowe could only agree with that assessment.

"He’s got to be my driver of the day to achieve what he did today," he said. (Reporting by Alan Baldwin, editing by Pritha Sarkar)