Pitcher needs to check the ball. If he doesn't like the ball or sees it is not the correct COR/COMP that the league specifies then he may ask the umpire to have the ball replaced.
Since the balls are team-supplied, this whole situation can be remedied by the plate umpire in the pre-game. How I do it is ask the teams for the game balls before the game starts and for a backup from each team. If 1 or both teams do not have a backup, then we go with what we have. No other balls are allowed to be put into play going forward. This prevents the "oh, here's one in my bag I forgot about" after their hitter fouls off the 2 game balls...
dustyjoe23 said:
I know in co-ed if the wrong ball is pitched you can either take the result of the play or redo with the correct ball.
This rule actually pertains to the size ofthe ball, not the COR/Comp of the ball. If a female batter is pitched a 12" ball and it is discovered before the next pitch then she may assume the count prior to the wrong ball being used OR take the result of the play.