The Serb, who will surrender the top spot to Nadal when the new rankings are published on Monday, secured one break in each set on his way to victory in Beijing.
Nadal, who won the French Open and US Open this year, failed to manufacture a break point as his run of 21 matches unbeaten came to an end.
But despite his victory, Australian Open champion Djokovic was quick to praise Nadal as being more-than-worthy of reclaiming the ranking from him.
“I have to say congratulations to Rafa because he deserves definitely to be number one of the world this year with the season that he has had,” admitted Djokovic after the match.
“He is the best player so far in 2013, there is no question about it.
“I am just very happy to be able to continue to play well and hopefully I can maintain the rhythm.”
Meanwhile, Nadal, who has not held the top ranking since 2011, admitted that he was not at his best on Sunday.
“I didn’t play my best match this afternoon,” said Nadal. “He played at a greater level with his serve. I was not able to have any chance when I was returning during the whole match.
“He was able to hit all the balls where he wanted to hit them, so when that is happening against a player like Novak you are dead.”
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