Singapore GP - Valtteri Bottas: Williams steering issue hurt tyres

The Finn was running in seventh place on the final lap when his tyres dramatically fell away, allowing a train of rivals past through the tight right-hand Turn 14 as he lost all grip. He eventually finished 11th.

With team-mate Felipe Massa having made it to the end in fifth place, Bottas thinks that a steering issue that hit him in the safety car period accounted for the disparity in their tyre wear.

"The rate of degradation was getting bigger and bigger and the last lap was a bit too much," he said.

"I had to defend the inside for that corner and, when I braked, there was no grip in the rear and it was the same on the exit. There was no traction.

"I couldn't manage the tyres as well as I wanted because I had a problem with the steering."

Bottas said that the steering issue left him with no feeling for what his car was doing in corners, among other issues.

"We still need to investigate if it was the power steering or some bearing," he said.

"The steering wheel was really sticky and there was no feedback from the car.

"If I was to turn on the straight it would stay there and not come back.

"I just couldn't feel those little snaps on the exits, so I felt I couldn't do a perfect job managing the tyres because of the issue with the steering."