NBA 2K13 Association management help

Hi I am currently managing the Orlando Magic, after cheating our budget we have gotten some of the best players (85+ rating), however their rating seem to always decrease despite all the practicing. Can someone please tell me how to improve player ratings?? Some of my players have lost up to 10 ratings.

If you put a star player/ starter to the bench he will usually start to get disappointed and finally lose ratings. Just like in realy life. Imho you could cheat if you edit the player roles before starting the association.