Valtteri Bottas makes "progress" with back injury

Valtteri Bottas has revealed that he is making "progress" as he battles to be fit to race at next weekend's Malaysian Grand Prix.

The Williams driver missed the opening race of the season after tearing a disc in his back in qualifying for the Australian Grand Prix last week.

The Finn tweeted: "Progress is made and every day is a step forward. Can't wait for Malaysia."

Bottas finished fourth in the drivers' standings in 2014.