F1 testing: Tuesday crash caught Red Bull's Gasly by surprise

Gasly, making his debut at the wheel of Red Bull's new Honda-powered RB15 after Max Verstappen drove it during a filming-day shakedown and on day one of the test, crashed at the long Turn 12 right-hander with just over an hour of the afternoon session left.

The car snapped out of control as he went through the corner, and the Frenchman spun rear-end-first into the tyre wall.

Gasly admitted the crash was caused by driver error when asked to explain it.

"Basically, you are pushing the car to the limits and playing with the limits," he said.

"I went on throttle and lost the rear, and basically that was it.

"It caught me a bit by surprise and [there's] not much you can do once it is done. We have six more days of testing and a lot of stuff to test."

Gasly insisted his first day in the Rb15 had been a "very positive" one despite the crash.

He finished the day with 92 laps to his name and a best time of 1m19.814s on the C3 tyre.

That was the seventh-fastest time on the day and was four tenths short of what Verstappen managed on Monday.

"I was really excited to be back behind the wheel," added Gasly. "We did some positive tests over the day.

"I felt very comfortable in the car. We feel there is some really good potential.

"We need to understand our package more but the first feedback is good."

Gasly, who drove a Honda-engined Toro Rosso car last year, praised the reliability the Japanese manufacturer's power units have shown over the first two days of the test.

"So far it has been really good," he said.

"Also looking at Toro Rosso, they have managed to do a lot of laps [209 over two days] so we need to use all the feedback.

"But so far we are really happy with the job they [Honda] have done. [There are] still more tests to do over the next six days but really happy so far."