LONDON • Spain's Rafael Nadal has pulled out of next week's ATP Tour Finals in London due to injury, so Novak Djokovic will end the year as world No. 1, having returned to the top of the rankings on Monday.
French Open champion Nadal announced on Monday that the abdominal muscle problem which prevented him from playing in the Paris Masters last week and ankle surgery had forced him to pull out of the season finale.
"I had the abdominal problem in Paris last week and have an issue in the ankle joint that has to be removed in the operating room," the 17-time Grand Slam winner wrote on Twitter. "This way, I hope to be in full condition for next season."
And his surgeon yesterday confirmed that the "intervention had been normal" and the operation was a success.
"Rafa Nadal has undergone arthroscopic surgery on his right ankle," said Dr Angel Ruiz-Cotorro.
American John Isner will take the 32-year-old's place in London when the Finals get under way on Sunday.
Japan's Kei Nishikori has also been drafted in to replace Argentinian Juan Martin del Potro, who pulled out following a knee injury.
Djokovic will become the first player since ATP rankings were introduced in 1973 to end the year on top of tennis' summit having been outside the top 20 during the same season.
"Reflecting on what I've been through in the last year, it's quite a phenomenal achievement," said the 14-time Grand Slam champion.
"And of course, I'm very, very happy and proud about it. I always believe in myself, but it was highly improbable at that time considering my ranking, and the way I played and felt on the court."
Having missed the second half of last season because of his troublesome elbow, Djokovic returned at the start of this year only for the injury to flare up again at the Australian Open in January.
He opted for surgery and was dumped out of the French Open as the 20th seed at the quarter-final stage before embarking on a fine run.
He beat Nadal in a Wimbledon semi-final thriller before ending a two-year Grand Slam drought by defeating Kevin Anderson in the final.
A few weeks later, he beat del Potro to win the US Open and claimed the Shanghai Masters title last month without dropping a set.
"What Novak achieved this season will go down as one of the great sporting comebacks. It's a phenomenal return to form that would have been hard to imagine just six months ago," said ATP executive chairman and president Chris Kermode.