Novak Djokovic has withdrawn from his scheduled appearances in the International Premier Tennis League, citing the effects of a busy season in which he went 82-6.
The world No. 1 had been supposed to play for the team from Singapore in the five-city league, including a match against Roger Federer.
"I had a great experience in the inaugural edition of the IPTL and was eagerly looking forward to playing in the second season, especially in front of the home crowd in Singapore," said Djokovic in a statement. "It’s been a long year for me and my body needs some extra time to recover."
Djokovic won 11 titles this season, including the ATP World Tour Finals two weeks ago.
Andy Murray and Stanislas Wawrinka will substitute for Djokovic. Murray will play fresh off his Davis Cup victory, while Wawrinka will be appearing in the off-season league for the first time. Federer, Rafael Nadal, Serena Williams, and Maria Sharapova are among the other top names playing.
The IPTL begins this week in Japan, and has expanded to five teams in the second year of the league. The next stop will be the Philippines, followed by New Delhi, Dubai, and Singapore.