Starting pitchers can pitch up to 10 innings in one game.  After starting a game, a pitcher cannot pitch again in the next four games. If a starting pitcher is sent to the minor leagues, he cannot return for 9 games. Only pitchers with blue cards can be starting pitchers. If you remove a pitcher from your starting rotation, he cannot pitch in relief for the next four games after his last start.

Relief Pitchers (blue cards) can pitch 9 innings in any stretch of 5 games. A relief pitcher must not have pitched in the previous four games to add him to the starting rotation. 

Relief Pitchers (red cards) pitchers with red cards can only pitch in relief. They can pitch 7 innings in any stretch of 5 games and cannot pitch any more than 2 innings in any single game.

Any relief pitcher sent to the minors cannot return until 4 games have been played.

Any pitcher that exceeds their allowable innings, must roll the injury dice after each additional inning pitched.