Since his season will be finishing early for that reason, he is making the most of the extra time off to go for surgery on an ongoing ankle issue.
The Spaniard's absence from London means 14-time Grand Slam champion Djokovic will end the year as the world number one for the fifth time in his career: level with Roger Federer and Jimmy Connors, and one behind Pete Sampras.
Novak Djokovic will begin the week as the top-ranked men's singles player in the world, but it was not the ideal ending he anticipated after suffering a shock loss to Karen Khachanov in the final of the Roles Masters in Paris on Sunday.
Nadal - who has not featured on the ATP Tour since retiring ahead of his semi-final with Juan Martin del Potro at the US Open in September - posted an update to Twitter on Wednesday morning (AEDT), confirming he had returned following procedure. Only Dominic Thiem at the Madrid Open and Novak Djokovic at Wimbledon beat Nadal in a match that went the distance. "Five months ago, it was highly improbable considering my ranking and the way I played and felt on the court".More news: Chris Watts: Dad admits to killing family to avoid death penalty
The 32-year-old took to social media to announce that ongoing abdominal and ankle injuries have brought his season to an end.
Djokovic moved up from No. 2 to overtake Rafael Nadal on Monday.
He also quit at the 2006 and 2007 French Opens at the third round and quarter-final stages respectively, while at the 2009 Australian Open, where he was defending champion, he pulled out of his quarter-final with Andy Roddick citing heat exhaustion.
So yes, the Swiss legend, Roger Federer and the invincible man from Serbia, Novak Djokovic hold the crest at the tournament.More news: Michigan Voters Legalize Marijuana
It looks like the best possible draw for Federer, who has added another remarkable year, winning yet another Grand Slam in Australia.
He should be feeling pretty good about his game right now and would be looking forward to reversing the results of his last year's showing in London where he was unable to win a match.
However, Nadal's primary focus once again next year may well be the clay season.
Nadal lost only four matches this year out of 49.More news: Nokia 9 leaks out boasting five rear cameras
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