Codes:
Pause a game, enter the options menu and enter on of the following codes. The sound of a click will confirm correct code entry. Exit the options menu, and select the resume game option. Press A to display a secret options menu. Some choices require another code to be entered. Press Left or Right to change the various settings.

Invisible walls
Press B(3), Z, A(3), Z. No out of bounds rule.

Curve ball
Press Z, A, B, Z, B(2).

Crazy ball
Press B, A, Z, B(2), Z, A, B.

Super power
Press Z, A, Z(8).

Super goalie
Press A(5), Z(5).

Super offense
Press A(5), Z, B.

Super defense
Press Z(5), B, Z.

Shootout
Press A, Z, A, B, A, Z. Game proceeds to shootout.

Stupid team
Press A, Z, B, A, Z, B.

Dream team
Press A(2), Z(2), B(2), A(2).