Williams F1 driver Valtteri Bottas says his back pain is manageable

Bottas suffered a small tear in a disc in his back during Melbourne qualifying and was not cleared to race next day.

He passed fitness tests prior to this weekend's event in Malaysia, and also made adjustments to his cockpit set-up to try to prevent a repeat of the problem.

Asked by AUTOSPORT how much discomfort he was in, Bottas replied: "I cannot say it's completely pain-free but the feelings are what we expected really.

"I feel it a little bit but the main thing is it was not getting any worse so it was very consistent during the day.

"I don't mind a bit of pain. It's not [distracting].

"I can still apply the maximum brake pressure, even on the long run I could brake well without any increased pain. "So I'm confident for the weekend because there is still much more painkillers that I can take, I haven't taken much."

Bottas added that the adjustments to his seating position had not affected his braking feel.

"It was pretty normal," he said. "We had a quite different pedal position and I got used to it immediately so it was no problem at all. Nothing new."

Williams was fifth and sixth overall on Friday with Felipe Massa and Bottas, as Ferrari again emerged as Mercedes' main rival.

"It looks like Ferrari is maybe a little bit stronger here than expected," said Bottas,

"We know we can improve a lot for tomorrow, we can still improve the car balance and obviously take out the fuel and turn up the engine.

"Whether it's going to be enough, I don't know."