All-Star Baseball 2003 Cheats for Gameboy Advance
Left handed hitter at bat:
R + Left gently, and R + Down gently before the pitch.
Right handed hitter at bat:
R + Right (gently), and R + Down (gently) before the pitch.
To unlock everything press L1 L2 R2 X O X SQUARE AND THEN Yyou will get everything so try it will work.