Louis van Gaal has acknowledged there is little he can do to keep Manchester United goalkeeper David de Gea at Old Trafford should he want to leave.
Spain keeper De Gea has been in fine form for United this term but, with his contract due to end at the close of next season, Real Madrid have regularly been linked with a move for the 24-year-old.
Van Gaal stated that while a generous offer has been made to De Gea in an attempt to keep him at United, the player himself was likely to call the shots.
"It takes a long time now," Van Gaal said.
"It can always happen. I am not the boss. I want him to stay. The player is the boss - he can say yes or no.
"You will have to ask David de Gea, not me. He has to sign. We have offered him a lot of money."
United have been heavily linked with moves for PSV's Memphis Depay and Borussia Dortmund midfielder Ilkay Gundogan this week, while rumours continue about the potential arrival of the Gundogan's team-mate Mats Hummels.
However, Van Gaal stated any incoming transfer movement at Old Trafford would be decided largely by players themselves.
Asked about the possibility of completing transfers before the close-season friendlies begin, he added: "We have to wait and see, it's dependable on the market. We shall also sell players and that's dependable on the market.
"It's not so easy to finalise all the decisions you are making because the players are the boss, not the manager.
"Every time you read in the papers that I buy that player or that player or have communicated with that player, it is not like that.
"At the end the player has to decide and not the manager and not the manager of the selling club."