Everton boss Roberto Martinez has warned Manchester United's David Moyes off Leighton Baines and Marouane Fellaini.
United have had their own difficulties over the summer, most notably concerning the future of Wayne Rooney, and Martinez alluded to the that as he responded to Moyes' remarks.
The Spaniard said: "I think my comment is quite clear. If managers start talking about players who are registered at other clubs, that is the end of the whole thing.
"I think everyone should look after their own things internally.
"I am sure they have got many issues in the same manner and I could easily come out and give my opinions about these players but I will be more respectful than that.
"The business should be done quietly. It is really unfortunate when you read papers and people talk about your players.
"I could sit down and give you half an hour with my vision of how the other club is being run, the players they want to go and how they should be sending messages to all the clubs around the world that they have been trying to sign players and haven't been able to do it.
"Everyone has got a price (but) when you invest money in a player and five years later you get offered the same money after performing really well, that becomes a little bit of a nonsense.
"The last thing I want is to get into a media war with a manager I really respect."
