Rafael Nadal has pulled out of next week's Paris Masters to concentrate on the ATP World Tour Finals in London and the Davis Cup final.
The Spaniard said on Facebook that he had withdrawn "to prepare well for the end of this season and also for 2012".
Nadal, the second seed for the event, has not played since he lost to Florian Mayer in Shanghai in mid-October.
He is one of five players who have qualified for this month's Tour Finals at London's O2 Arena.
Novak Djokovic, Andy Murray, Roger Federer and David Ferrer are also through to the eight-man finals, with Tomas Berdych, Jo-Wilfried Tsonga and Mardy Fish leading the chase for the remaining three places.
Nadal, who has not specified the nature of the injury behind his withdrawal, is also due to represent Spain in their Davis Cup final against Argentina in Seville, starting on 28 November.
He has never won the Paris title and described the decision to withdraw as "difficult", adding: "I hope I can be back in 2012 to that great event in the most beautiful city in the world, and hopefully try to win it one day."
World number one Novak Djokovic continued his progress at the Swiss Indoors in Basle on Thursday, beating qualifier Lukas Kubot of Poland 6-1 6-2 to reach the quarter-finals.
Seventh seed Andy Roddick beat Radek Stepanek 2-6 6-3 6-3 to set up a meeting with Roger Federer on Friday.