Djokovic, winner of the last three Grand Slam tournaments, is now over 3,000 points clear of old rival Nadal despite a quarterfinal defeat by Daniil Medvedev in the Principality last week, AFP reported.
World number two Nadal dropped ranking points after his title defense ended with a shock semifinal loss to eventual champion Fabio Fognini.
The 31-year-old Italian reached a career-high ranking of 12th after claiming his maiden Masters trophy with a straight-sets win over unheralded Serbian Dusan Lajovic in Sunday's final.
Fognini jumped six spots to close on the top 10, while Lajovic climbed 24 places to 24th.
ATP top 20
1. Novak Djokovic (SRB) 11,160pts
2. Rafael Nadal (ESP) 8,085pts
3. Alexander Zverev (GER) 5,770pts
4. Roger Federer (SUI) 5,590pts
5. Dominic Thiem (AUT) 4,675pts
6. Kevin Anderson (RSA) 4,115pts (+1)
7. Kei Nishikori (JPN) 3,690pts (-1)
8. Stefanos Tsitsipas (GRE) 3,240pts
9. Juan Martin del Potro (ARG) 3,225pts
10. John Isner (USA) 3,085pts