There is always the risk of players fouling out if u try and play them 48 minutes a game. Hopefully this improves by training ID but there is also the chance that the player is aggressive and more foul prone. You also need to use Strictly follow Depth Chart, Let them play for foul trouble, have the player as starter, backup and reserve and make sure you don't have any spare players on your bench. So u would usually have 8 players a game (PG, SG, SF and their backups, plus your trainee PF and C).