Roberto Martinez thinks that is is unfair that the transfer window is open during the Premier League season.
The Everton manager made the comments on Sky Sports' Monday Night Football programme where he was standing in for regular host Gary Neville.
The remarks come as Chelsea look set to make a fresh £30m bid for Martinez's star defender John Stones.
Everton will have played four league games by the time the transfer window does eventually shut on September 1, and Martinez faces a battle to keep hold of Stones until then.
"The window, when it's open and you have to prepare official games, is very, very unfair. I don't think it's right," said Martinez.
"I think we should be just having a period where you can assemble your squad, then once the first league game starts, everyone is focused.
"I think we're forgetting footballers have a human side and that really can affect [them]. The other side is we are the ones that in a brave approach are giving young players opportunities.
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"Players like John Stones and Ross Barkley have an incredible future, and these players are going to attract interest from the outside.
"As a football club, these players are going to be part of our success in the future."
Martinez was standing in for Neville who was absent following the sudden death of his father Neville Neville.