Nadal has 11,160 points, just 40 ahead of Djokovic, who lost his grip on the top spot despite defeating the Mallorcan to win the China Open on Sunday.[break]
Britain´s Andy Murray, currently recuperating from back surgery, is third in the revised rankings but Swiss great Federer sinks one place from sixth to seventh.
Spain´s David Ferrer remains at number four, just 185 points off Murray´s tally, while Argentina´s Juan Martin del Potro moves up two places to fifth after winning the Japan Open.
Since returning in February after seven months out with a left knee injury, Nadal, 27, has won 10 titles, including the French Open and US Open.
Until Sunday´s loss to Djokovic, he had been unbeaten since Wimbledon, where he was a shock first-round loser to Belgium´s Steve Darcis.
Nadal has previously had two stints at the summit of men´s tennis. He first became number one in August 2008 and stayed there for 46 weeks, regaining top spot in June 2010 and adding 56 weeks to his tally.
ATP world rankings
1 Nadal, Rafael (ESP) 11,160 (+1)
2 Djokovic, Novak (SRB) 11,120 (-1)
3 Murray, Andy (GBR) 6,895
4 Ferrer, David (ESP) 6,710
5 Del Potro, Juan Martin (ARG) 4,925 (+2)
6 Berdych, Tomas (CZE) 4,610 (-1)
7 Federer, Roger (SUI) 4,515 (-1)
8 Wawrinka, Stanislas (SUI) 3,150 (+1)
9 Tsonga, Jo-Wilfried (FRA) 3,115 (-1 0
10 Gasquet, Richard (FRA) 3,095
11 Raonic, Milos (CAN) 2,815
12 Haas, Tommy (GER) 2,355
13 Isner, John (USA) 2,115 (+3)
14 Simon, Gilles (FRA) 2,095
15 Janowicz, Jerzy (POL) 2,060
16 Almagro, Nicolas (ESP) 2,030 (+1)
17 Fognini, Fabio (ITA) 1,885 (+2)
18 Nishikori, Kei (JPN) 1,840 (-5)
19 Robredo, Tommy (ESP) 1,830 (-1)
20 Anderson, Kevin (RSA) 1,775 (+1)
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