| Men's singles | |
|---|---|
| 2003 AIG Japan Open Tennis Championships | |
| Champion |  Rainer Schüttler |
| Runner-up |  Sébastien Grosjean |
| Score | 7–6(7–5), 6–2 |
| Draw | 48 (6 Q / 4 WC ) |
| Seeds | 16 |
Kenneth Carlsen was the defending champion but lost in the third round to Hyung-Taik Lee.
Rainer Schüttler won in the final 7–6(7–5), 6–2 against Sébastien Grosjean.
All sixteen seeds received a bye to the second round.
Rainer Schüttler (champion) Sébastien Grosjean (final)
Paradorn Srichaphan (semifinals)
Jiří Novák (third round)
Mark Philippoussis (quarterfinals) Nicolas Kiefer (third round)
Hyung-Taik Lee (quarterfinals)
Jan-Michael Gambill (quarterfinals)
Kenneth Carlsen (third round)
Mario Ančić (third round)
John van Lottum (second round) Brian Vahaly (second round)
Wesley Moodie (second round) Lars Burgsmüller (second round) Grégory Carraz (second round)| Semifinals | Final | ||||||||||||
| 1 | Rainer Schüttler | 6 | 6 | ||||||||||
| Cyril Saulnier | 3 | 2 | |||||||||||
| 1 | Rainer Schüttler | 77 | 6 | ||||||||||
| 2 | Sébastien Grosjean | 65 | 2 | ||||||||||
| 3 | Paradorn Srichaphan | 6 | 3 | 4 | |||||||||
| 2 | Sébastien Grosjean | 4 | 6 | 6 | |||||||||
| First round | Second round | Third round | Quarterfinals | ||||||||||||||||||||||||
| 1 | R Schüttler | 6 | 6 | ||||||||||||||||||||||||
| WC |  S Iwabuchi | 77 | 6 | WC | S Iwabuchi | 0 | 4 | ||||||||||||||||||||
| C Mamiit | 64 | 2 | 1 | R Schüttler | 6 | 6 | |||||||||||||||||||||
| R Kendrick | 77 | 6 | R Kendrick | 3 | 2 | ||||||||||||||||||||||
| W Arthurs | 63 | 4 | R Kendrick | 6 | 3 | 6 | |||||||||||||||||||||
| 13 | B Vahaly | 2 | 6 | 4 | |||||||||||||||||||||||
| 1 | R Schüttler | 6 | 6 | ||||||||||||||||||||||||
| S Draper | 3 | 3 | |||||||||||||||||||||||||
| LL | E Taino | 2 | 65 | ||||||||||||||||||||||||
| Q | J Vacek | 3 | 64 | S Draper | 6 | 77 | |||||||||||||||||||||
| S Draper | 6 | 77 | S Draper | 7 | 6 | ||||||||||||||||||||||
 I Heuberger | 2 | 61 | 6 | N Kiefer | 5 | 2 | |||||||||||||||||||||
| A Bogomolov Jr. | 6 | 77 | A Bogomolov Jr. | 5 | 67 | ||||||||||||||||||||||
| 6 | N Kiefer | 7 | 79 | ||||||||||||||||||||||||
| First round | Second round | Third round | Quarterfinals | ||||||||||||||||||||||||
| 4 | J Novák | 77 | 6 | ||||||||||||||||||||||||
| Q | B Phau | 61 | 77 | 77 | Q | B Phau | 62 | 2 | |||||||||||||||||||
| J Salzenstein | 77 | 64 | 63 | 4 | J Novák | 6 | 5 | 4 | |||||||||||||||||||
| J Gimelstob | 65 | 6 | 1 | C Saulnier | 4 | 7 | 6 | ||||||||||||||||||||
| C Saulnier | 77 | 3 | 6 | C Saulnier | 78 | 77 | |||||||||||||||||||||
| 15 | L Burgsmüller | 66 | 64 | ||||||||||||||||||||||||
| C Saulnier | 5 | ||||||||||||||||||||||||||
| 5 | M Philippoussis | 2r | |||||||||||||||||||||||||
| 10 | M Ančić | 6 | 7 | ||||||||||||||||||||||||
 W Eschauer | 0 | 4 | Q | T Iwami | 2 | 5 | |||||||||||||||||||||
| Q | T Iwami | 6 | 6 | 10 | M Ančić | 4 | 5 | ||||||||||||||||||||
 F Browne | 6 | 6 | 5 | M Philippoussis | 6 | 7 | |||||||||||||||||||||
| WC | T Terachi | 3 | 4 | F Browne | 4 | 3 | |||||||||||||||||||||
| 5 | M Philippoussis | 6 | 6 | ||||||||||||||||||||||||
| First round | Second round | Third round | Quarterfinals | ||||||||||||||||||||||||
| 7 | H-T Lee | 6 | 63 | 6 | |||||||||||||||||||||||
| Q | G Weiner | 4 | 2 |  F Verdasco | 3 | 77 | 3 | ||||||||||||||||||||
| F Verdasco | 6 | 6 | 7 | H-T Lee | 6 | 6 | |||||||||||||||||||||
| M Vassallo Argüello | 0 | 3 | 9 | K Carlsen | 3 | 4 | |||||||||||||||||||||
| WC | G Motomura | 6 | 6 | WC | G Motomura | 2 | 64 | ||||||||||||||||||||
| 9 | K Carlsen | 6 | 77 | ||||||||||||||||||||||||
| 7 | H-T Lee | 6 | 65 | 3 | |||||||||||||||||||||||
| 3 | P Srichaphan | 4 | 77 | 6 | |||||||||||||||||||||||
| 14 | W Moodie | 1 | 63 | ||||||||||||||||||||||||
| A Waske | 65 | 3 | WC | T Suzuki | 6 | 77 | |||||||||||||||||||||
| WC | T Suzuki | 77 | 6 | WC | T Suzuki | 2 | 63 | ||||||||||||||||||||
 D Norman | 7 | 6 | 3 | P Srichaphan | 6 | 77 | |||||||||||||||||||||
| Q | G Bastl | 5 | 4 | D Norman | 6 | 63 | 62 | ||||||||||||||||||||
| 3 | P Srichaphan | 4 | 77 | 77 | |||||||||||||||||||||||
| First round | Second round | Third round | Quarterfinals | ||||||||||||||||||||||||
| 8 | J-M Gambill | 6 | 6 | ||||||||||||||||||||||||
 I Miranda | 6 | 4 | 4 | B Ulihrach | 3 | 4 | |||||||||||||||||||||
| B Ulihrach | 2 | 6 | 6 | 8 | J-M Gambill | 6 | 7 | ||||||||||||||||||||
| T Berdych | 62 | 6 | 3 | Q | M Kratochvil | 3 | 5 | ||||||||||||||||||||
| Q | M Kratochvil | 77 | 4 | 6 | Q | M Kratochvil | 6 | 6 | |||||||||||||||||||
| 12 | J van Lottum | 2 | 3 | ||||||||||||||||||||||||
| 8 | J-M Gambill | 3 | 64 | ||||||||||||||||||||||||
| 2 | S Grosjean | 6 | 77 | ||||||||||||||||||||||||
| 16 | G Carraz | 5 | 6 | 5 | |||||||||||||||||||||||
 A Vinciguerra | 6 | 4 | 1 | D van Scheppingen | 7 | 1 | 7 | ||||||||||||||||||||
| D van Scheppingen | 4 | 6 | 6 | D van Scheppingen | 3 | 63 | |||||||||||||||||||||
| R Söderling | 4 | 4 | 2 | S Grosjean | 6 | 77 | |||||||||||||||||||||
| I Karlović | 6 | 6 | I Karlović | 3 | 68 | ||||||||||||||||||||||
| 2 | S Grosjean | 6 | 710 | ||||||||||||||||||||||||
Pete Sampras defeated Andre Agassi in the final, 6–3, 6–4, 5–7, 6–4 to win the men's singles tennis title at the 2002 US Open. It was his fifth US Open title and his all-time record-extending 14th major title overall. The final was a rematch of the 1990 and 1995 US Open finals, where Sampras won his first and seventh major titles respectively. It was Sampras' last professional appearance, though he did not officially declare his retirement until 2003. Sampras became the only man in the Open Era to win the final major he played.
Andre Agassi defeated Rainer Schüttler in the final, 6–2, 6–2, 6–1 to win the men's singles tennis title at the 2003 Australian Open. It was his fourth Australian Open title and his eighth and last major title overall. With the win, Agassi claimed his 21st consecutive match win at the Australian Open, as he won the title in 2000 and 2001.
Roger Federer defeated the defending champion Andy Roddick in the final, 7–5, 6–3 to win the men's singles tennis title at the 2004 Canadian Open.
Andy Roddick defeated David Nalbandian in the final, 6–1, 6–3 to win the men's singles tennis title at the 2003 Canada Masters.
Stefan Koubek was the defending champion but lost in the second round to Hyung-Taik Lee.
Defending champion Andre Agassi defeated Roger Federer in the final, 6–3, 6–3, 3–6, 6–4 to win the men's singles tennis title at the 2002 Miami Open.
Carlos Moyá defeated Lleyton Hewitt in the final, 7–5, 7–6(7–5) to win the singles tennis title at the 2002 Cincinnati Masters.
Defending champion Lleyton Hewitt defeated Gustavo Kuerten in the final, 6–1, 6–1 to win the men's singles tennis title at the 2003 Indian Wells Masters. Hewitt saved three match points in his first round encounter against Younes El Aynaoui.
Félix Mantilla defeated Roger Federer in the final, 7–5, 6–2, 7–6(10–8) to win the men's singles tennis title at the 2003 Italian Open.
Guillermo Coria defeated Agustín Calleri in the final, 6–3, 6–4, 6–4 to win the singles tennis title at the 2003 Hamburg European Open.
Juan Carlos Ferrero defeated Nicolás Massú in the final, 6–3, 6–4, 6–3 to win the singles tennis title at the 2003 Madrid Open.
Tim Henman defeated Andrei Pavel in the final, 6–2, 7–6(8–6), 7–6(7–2) to win the singles tennis title at the 2003 Paris Masters.
Guillermo Coria defeated Rainer Schüttler in the final, 6–2, 6–1, 6–3 to win the singles tennis title at the 2004 Monte Carlo Masters.
Sjeng Schalken was the defending champion but lost in the quarterfinals to Michel Kratochvil.
Lleyton Hewitt was the defending champion but lost in the quarterfinals to Paradorn Srichaphan.
Greg Rusedski was the defending champion but lost in the second round to Scott Draper.
Sébastien Grosjean was the defending champion but lost in the quarterfinals to Àlex Corretja.
Hyung-Taik Lee was the defending champion but did not compete that year.
Andy Roddick was the defending champion, but lost in the quarterfinals.
Rainer Schüttler was the defending champion, but did not participate.