Rafael Nadal has withdrawn from next week's Swiss Indoors tournament in Basel citing fatigue.
Nadal, who recently regained the world No 1 ranking from Novak Djokovic, has played a gruelling schedule this season and hard courts seem to have most effect on his troublesome knees.
Back-to-back tournaments in Beijing and Shanghai, neither of which ended in titles, appear to have taken their toll and the Spaniard has opted to take a week off instead of travelling to Switzerland.
He has not played the Basel event since 2004 and has never won a match there.
He said on Facebook: "Hi all, sorry to announce that I won't travel to Basel in Switzerland but after very exhausting weeks I have to regroup my fitness and my body. I will do my best to come back to the Swiss Indoors next year."
Nadal is next scheduled to play in the Paris Masters next week and then travel to London for the season-ending Barclays ATP World Tour Finals in London.