If the player has every intention of leaving, get it sorted asap. Let your current club know asap, give them the courtesy of planning for the future. It never happens though cause the manager needs the current club to believe they're a chance of re-signing the player to create a false sense of value for the new club to try and begin a bidding war to jack up the players salary.
It totally sucks though. The player and manager both know there is no intention for them to stay but still string the current club along to manipulate the situation. It's what peed me off the most with Mitchell Moses, blind Freddy knew he was going, but the club gave him time because he didn't want to be rushed, so the club didn't push the issue cause they were scared they might lose him. In reality he was already out the door. Pull the contract tell the media so they report it, in an instant the disloyal sack of crap takes a 35 percent hit to his next deal because his new club doesn't have to bid against anyone. Stabbing people in the back works both ways, respect us we respect you. Stab us in the back, we make sure the knife's twisted in urs before our time togeather is done.