EA Dream Team
Type "1212 [Ctrl] at the team selection screen. The EA Dream Team will appear as the thirty-third team on the list.
EA underwear Dream Team
Type "1212 [Shift] [Ctrl] at the team selection screen. The EA Dream Team will play in their underwear.
Cornfield stadium
Press [Up] [Down] [Right] [Up] [Down] [Left] [Up] at the stadium selection screen.
Mystery stadium
Press [Right] [Left] [Up] [Left] [Down] [Right] [Left] at the stadium selection screen.
All bonus stadiums
Type "1212 [Ctrl] 21" at the stadium selection screen. The Cornfield, Ebbetts Field, and the Polo Grounds will be selectable.
Hit home runs
Hold 1 + 2 + 3 + 4 and press [Up] [Space] [Left] [Right] [Shift] [Alt] [Ctrl]. Then press [Shift] + [Up] to hit the ball. Alternatively, hold 1 + 2 + 7 while hitting the ball.
Cheering crowd
Hold 1 + 2 + 3 + 4 and press [Down] [Ctrl] [Down] [Ctrl] [Space].
Instant win
The "belikethephillies" during game play.