"I can't guarantee any player that he will play always," said the Liverpool boss. "They know my idea is to use the right player for the right game so if Craig is an option for 10 games I will try to use him for 10 games.
"But if I have to use Robbie Fowler and Peter Crouch in others I will, because I'm always thinking about the team.
"The players need to understand when you play 60 games or, I hope, more next season, it means you need a lot of players and they cannot play every game at the same level.
"You need to use different players and if they understand that if you want to win trophies, or at least to try to win every trophy, we need players always fit and always ready.
"So if you are a good player and are tired we can have another one as good as you and, if he's fitter, it's better to use this player.
"Sometimes it's not easy to tell a player he's on the bench because he is disappointed but they are professionals and they know the most important thing is the team."