2003 Tennis Masters Cup – Singles

Roger Federer defeated Andre Agassi in the final, 6–3, 6–0, 6–4 to win the singles tennis title at the 2003 Tennis Masters Cup. It was the first of an eventual then-record six Tour Finals titles for Federer.

Lleyton Hewitt was the reigning champion, but did not qualify this year.

Seeds
A champion seed is indicated in bold text while text in italics indicates the round in which that seed was eliminated.

• # 🇺🇸 Andy Roddick (semifinals)

• # 🇪🇸 Juan Carlos Ferrero (round robin)

• # Roger Federer (champion)

• # 🇦🇷 Guillermo Coria (round robin)

• # 🇺🇸 Andre Agassi (final)

• # 🇩🇪 Rainer Schüttler (semifinals)

• # 🇪🇸 Carlos Moyá (round robin)

• # 🇦🇷 David Nalbandian (round robin)

Alternate
• # 🇦🇺 Mark Philippoussis (Did not play)

Red group
''Standings are determined by: 1. number of wins; 2. number of matches; 3. head-to-head records in two-player ties; 4. in three-player ties, percentage of sets won, or of games won; 5. steering-committee decision.''

Blue group
''Standings are determined by: 1. number of wins; 2. number of matches; 3. head-to-head records in two-player ties; 4. in three-player ties, percentage of sets won, or of games won; 5. steering-committee decision.''