West Ham manager Slaven Bilic sympathises with Southampton counterpart Mauricio Pellegrino, who is dealing with want-away defender Virgil van Dijk.
The Dutch defender has submitted a transfer request to get his way, amid reported interest from Chelsea and Liverpool, and the Hammers boss believes that player power makes it tough for managers.
"I know that the power is too much on the side of the players and their agents," Bilic told reporters.
"The power is massive. And you can't say that we have to fight it. We have to live with it and we have to try to find the best possible solution for the club.
"That's why I say the football game is very simple but the manager's job is very complicated. Sometimes you win, sometimes you lose, on the pitch and off the pitch.
"Of course I have a lot of sympathy. It's hard for them, and sometimes you are on the other side of the story.
"Sometimes you are in the position that you are getting the player, but it definitely doesn't help. It doesn't help the managers."