Roger Federer has ousted Rafael Nadal as world number one in the latest ATP rankings published on Monday.

Nadal’s fall could be traced to his surprise quarter-final exit at the Madrid Masters, giving way to Federer, who returns to the top spot despite not having played since March.

Former world No. 1 Novak Djokovic slipped six places to 18th after his second round defeat in Madrid, his lowest ranking since October 2006.

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Madrid winner Alexander Zverev remains in third, but the man he beat in Sunday's final, Dominic Thiem, dropped a place to eighth despite knocking out Nadal on his way to facing Zverev.

ATP rankings as of May 14

1. Roger Federer (SUI) 8,670 pts (+1)

2. Rafael Nadal (ESP) 9,950 (-1)

3. Alexander Zverev (GER) 6,015

4. Grigor Dimitrov (BUL) 4,870

5. Marin Cilic (CRO) 4,770

6. Juan Martin Del Potro (ARG) 4,540

7. Kevin Anderson (RSA) 3,660 (+1)

8. Dominic Thiem (AUT) 3,545 (-1)

9. John Isner (USA) 3,305

10. David Goffin (BEL) 2,930

11. Pablo Carreno (ESP) 2,280

12. Sam Querrey (USA) 2,220 (+1)

13. Roberto Bautista (ESP) 2,210 (+1)

14. Jack Sock (USA) 2,155 (+1)

15. Diego Schwartzman (ARG) 2,130 (+1)

16. Lucas Pouille (FRA) 1,995 (+2)

17. Tomas Berdych (CZE) 1,980

18. Novak Djokovic (SRB) 1,905 (-6)

19. Kyle Edmund (ENG) 1,905 (+3)

20. Hyeon Chung (KOR) 1,807 (+1)

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