Nadal was beaten by Novak Djokovic in Sunday's final in China -- the fourth time in five years that Djokovic won the tournament.
But Nadal, by advancing to the finals, built up enough points to oust Djokovic and take over the No. 1 ranking. The loss in the China event was just his fourth of the year against 65 wins. He's won 10 tournaments and finished second three other times in 14 tournaments..
It is Nadal's third time atop the rankings. He first replaced Roger Federer as No. 1 on Aug. 18, 2008, and stayed on top for 46 weeks. He ousted Federer again on June 7, 2010, keeping the No. 1 spot for 56 weeks before Djokovic's first stint on top.
Nadal's 103rd week as No. 1, which is seventh most, began Monday. Djokovic totaled 101 weeks at No.1, tied with Andre Agassi for eighth-most. The record is held by Federer at 302 weeks.
Juan Martin del Potro won the Japan Open, beating Milos Raonic, and moves up from seventh to fifth in the rankings. He has been ranked as high as fourth (January 2010). It was del Potro's third ATP title of the year.
His move up forces Tomas Berdych down one spot to sixth and Federer into seventh. Federer's Swiss countryman Stanislas Wawrinka passes Jo-Wilfried Tsonga for the No. 8 rankings, which marks a career high for Wawrinka. Tsonga is now ninth.
Nine players in the Top 10 -- all except No. 3- Andy Murray, who is still nursing a back problem -- are entered into this week's Shanghai Rolex Masters. Djokovic beat Murray in last year's tournament finals.
The ATP Top 10 listing player's name, home country and ranking points:
1. Rafael Nadal, Spain, 11,160
2. Novak Djokovic, Serbia, 11,120
3. Andy Murray, Great Britain, 6,895
4. David Ferrer, Spain, 6,710
5. Juan Martin del Potro, Argentina, 4,925
6. Tomas Berdych, Czech Republic, 4,610
7. Roger Federer, Switzerland, 4,515
8. Stanislas Wawrinka, Switzerland, 3,150
9. Jo-Wilfried Tsonga, France, 3,115
10. Richard Gasquet, France, 3,095