World number one Rafael Nadal has withdrawn from the Swiss Indoors Basel due to a knee injury.

The 16-time grand slam champion was due to compete in the hard-court tournament in Switzerland next week, but on Tuesday revealed he is not fully fit.

Nadal's 16-match winning run came to an end with a defeat to old foe Roger Federer in the Shanghai Masters final last Sunday and he has been advised to take a break with the Paris Masters and ATP World Tour Finals on the horizon.