PARIS, May 7, 2018 (News Wires) - Croatia's Marin Cilic dropped a place to fifth in the ATP rankings released today after making an early exit from last week's Istanbul tournament. Former US Open champion Cilic, who lost in both last year's Wimbledon final and January's Australian Open final to Roger Federer, was bundled out by unseeded Tunisian Malek Jaziri after receiving a bye into the second round. Bulgarian Grigor Dimitrov took fourth spot despite not having played, with Spain's Rafael Nadal still atop the rankings. ATP rankings as of May 7, 2018: 1. Rafael Nadal (ESP) 8,770 pts 2. Roger Federer (SUI) 8,670 3. Alexander Zverev (GER) 5,195 4. Grigor Dimitrov (BUL) 4,950 (+1) 5. Marin Cilic (CRO) 4,780 (-1) 6. Juan Martin Del Potro (ARG) 4,470 7. Dominic Thiem (AUT) 3,545 8. Kevin Anderson (RSA) 3,345 9. John Isner (USA) 3,125 10. David Goffin (BEL) 3,020 11. Pablo Carreno Busta (ESP) 2,280 12. Novak Djokovic (SRB) 2,220 13. Sam Querrey (USA) 2,220 14. Roberto Bautista Agut (ESP) 2,175 15. Jack Sock (USA) 2,155 16. Diego Schwartzman (ARG) 2,085 17. Tomas Berdych (CZE) 2,060 18. Lucas Pouille (FRA) 1,995 19. Fabio Fognini (ITA) 1,840 20. Kei Nishikori (JPN) 1,835