Sega's acclaimed basketball series continues with a number of refinements to the game engine introduced in NBA 2K2. New player animations and moves support a retooled physics model allowing for smoother post-ups, comebacks on offense, and more realistic rebounding options once the ball hits the rim. Updated graphics include an ESPN-style presentation and minute details such as beads of sweat appearing on players the longer they remain on the court, offering players a visual cue to make substitutions. Crowds have also been updated so rows closest to the court feature 3D individuals rather than 2D sprites. Playable teams include all 29 NBA squads from the 2002 season, both 2002 All-Star teams, and four fantasy teams consisting of legends from the past.
Players can immediately jump into the action by choosing the Quick Game option, or select from the following six modes: Street, Franchise, Season, Playoffs, Tournament, and Practice. NBA 2K3 for GameCube does not support network play found on the Xbox or PlayStation 2 versions, but players can still participate in special "Sega Sports Challenge" games and then post their results on www.segasports.com via codes provided at the end of each competition. After creating a user profile, players can keep track of their stats in eleven different categories. Games played as part of the "Sega Sports Challenge" automatically use default rosters and settings to ensure parity.
Players can hit the asphalt in Street Mode with a minimum of two-on-two to a maximum of five-on-five action. Two fictional teams, the Ballers and Ringers, and nine playgrounds and gyms are available, each modeled after real-life venues from across the country. Street ball rules apply, meaning baskets are worth one point and shots outside what would normally be the three-point line are worth two. Other options include day or night games and adjustable weather such as fog, heat wave, and rain while playing outdoors. Choose carefully, however, since weather affects a player's performance as the game wears on. While the rest of the modes are the same as 2001's game, players have the added ability to import an NCAA College Basketball 2K3 class into Franchise mode.