Dele has just endured a disappointing time on loan in Turkey, making 10 appearances and scoring two goals, and was last month booed by fans while being substituted less than half an hour into a game.
Gunes has previously said Dele has fallen "below expectations" at the club and on Thursday, after leaving then player on the bench for a cup game, said the loanee "cannot contribute at the moment."
"His current situation did not meet our expectations in terms of team integrity," Gunes told reporters, reiterating his past comments.
"We will evaluate. I don't think Dele Alli deserves to play right now.
"Sending the player [back to Everton] is another thing and not the subject here. He has enjoyed a good career and we expect him to contribute to the team, but we think he cannot contribute at the moment.
"We will evaluate it with him and the club."