Carlos Alcaraz was confirmed on Monday as the youngest player to break into the ATP top five since Rafael Nadal after the teenager reached the Hamburg final over the weekend.
The 19-year-old Spaniard is the youngest man to achieve the feat since his illustrious compatriot first climbed into the top five in 2005 while still 18.
Alcaraz failed to win the clay-court title in Germany, though, losing to Italian youngster Lorenzo Musetti on Sunday despite saving five match points.
Musetti rose 31 places to 31st in the rankings and is now set to be seeded for the US Open, which starts on August 29.
Daniil Medvedev remains the world number one, with Wimbledon champion Novak Djokovic seventh after the grass-court Grand Slam tournament was stripped of ranking points for banning Russian and Belarusian players.
ATP top 20:
1. Daniil Medvedev 7,775 pts
2. Alexander Zverev (GER) 6,850
3. Rafael Nadal (ESP) 6,165
4. Stefanos Tsitsipas (GRE) 5,045
5. Carlos Alcaraz (ESP) 4,895 (+1)
6. Casper Ruud (NOR) 4,890 (-1)
7. Novak Djokovic (SRB) 4,770
8. Andrey Rublev 3,575
9. Felix Auger-Aliassime (CAN) 3,445
10. Jannik Sinner (ITA) 3,185
11. Hubert Hurkacz (POL) 3,025 (+1)
12. Taylor Fritz (USA) 2,960 (+1)
13. Cameron Norrie (GBR) 2,928 (-2)
14. Matteo Berrettini (ITA) 2,430 (+1)
15. Diego Schwartzman (ARG) 2,325 (-1)
16. Marin Cilic (CRO) 2,130
17. Reilly Opelka (USA) 2,055
18. Grigor Dimitrov (BUL) 1,740
19. Gael Monfils (FRA) 1,615 (+1)
20. Roberto Bautista Agut (ESP) 1,600 (-1)
Selected:
31. Lorenzo Musetti (ITA) 1,280 (+31)