Win the World Championship and save the game. Then at the exhibition mode character selection screen, press Square, then press Square again and Jackel, Goober, Rascal, and Beastman will be selectable.
Create a new boxer in "Main Event" mode, select, then immediately save a boxer to a memory card. Repeat this process to save a second Main Event boxer to the memory card. Then, begin a match in two player versus mode. Now at the character selection screen, press Square to choose one of the previously saved Main Event boxers.
At the two player versus mode character selection screen, press Square, then press Square again and the boxing trainer will be selectable.
Note: This trick requires a dual analog controller. Begin a match in main event mode. Press L3 or R3 to take a snapshot of the current scene. The photo that was snapped will appear in the newspaper at the end of the bout.
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