Ailing world No. 1 Novak Djokovic decided to pull out of next week's China Open, citing a back injury.

Djokovic overcame the injury en route to capturing his first-ever U.S. Open title earlier this month, but was forced to retire from a Davis Cup match against Argentine slugger Juan Martin del Potro two weeks ago, as his Serbian squad lost to visiting Argentina in a semifinal showdown in Belgrade.

The 24-year-old Djokovic captured the last two China Open titles, including a victory over Spaniard David Ferrer in last year's finale at Beijing Olympic Green Tennis Centre.

Djokovic ascended to No. 1 for the first time in his career this year, one in which he captured three quarters of the Grand Slam events.

The 2011 China Open will commence Monday in Beijing.