MLB Slugfest 20-03
Enter these codes when the match-up screen appears as your game is loading by pressing X, Y, and B the required amount of times shown in the Parenthesis (#) below. X changes the first position, Y changes the second position and B changes the third position. 

Log Bat: X (0) - Y (0) - B (4) Up
Rubber Ball: X (2) - Y (4) - B (2) Up
Extra Time: X (1) - Y (2) - B (3) Up
No Fatigue: X (3) - Y (4) - B (3) Up 
Rocket Park Stadium: X (3) - Y (2) - B (1) Up 
Roman Coliseum Stadium: X (3) - Y (3) - B (3) Up 
16 Softball: X (2) - Y (4) - B (2) Down 
Unlimited Turbo: X (4) - Y (4) - B (4) Down 
Tournament Mode: X (1) - Y (1) - B (1) Down 
Mace Bat: X (0) - Y (0) - B (4) Left 
Maximum Speed: X (0) - Y (0) - B (3) Left 
Maximum Power: X (0) - Y (3) - B (0) Left 
Maximum Batting: X (3) - Y (0) - B (0) Left
Small Heads: X (2) - Y (0) - B (0) Left 
Wiffle Bat: X (0) - Y (0) - B (4) Right 
Big Heads: X (2) - Y (0) - B (0) Right 
Pinto Team: X (2) - Y (1) - B (0) Right 
Eagle Team: X (2) - Y (1) - B (2) Right 
Lion Team: X (2) - Y (2) - B (0) Right
Horse Team: X (2) - Y (1) - B (1) Right
Todd McFarlane Team: X (2) - Y (2) - B (2) Right 
Terry Fitzgerald Team: X (3) - Y (3) - B (3) Right