Unlock Characters/Teams
On the "Enter Initials" screen, type the following codes. Then, go to the "Select Team" screen -- you should hear a confirming noise and you'll see unlocked characters in the teams list:
Player 1: ESP, Player 2: NSN - Unlock Michelle Beadle and Colin Cowherd.
Player 1: MAS, Player 2: COT - Unlock NBA Mascots.
Player 1: MJT - Unlock Tim Kitzrow (Announcer) and Mark Turmell (Developer).
Player 1: ADI, Player 2: DAS - Unlock Team Adidas.
Player 1: JOR, Player 2: DON - Unlock Team Jordon.
Player 1: SPR, Player 2: ITE - Unlock Team Sprite.