Newcastle United boss Alan Pardew believes that agents' behaviour may need to be addressed by the Football Association.
The Magpies brought in six players in the January transfer window including Moussa Sissoko and Mapou Yanga-Mbiwa from French sides Toulouse and Montpellier respectively.
Pardew said in his programme notes: "Agents have a habit of moving the goalposts when you feel a deal is close, so it is a difficult business to be a part of.
"I echo the view of QPR boss Harry Redknapp earlier in the week that some of the things going on are not right, and maybe the behaviour of agents is something the game's authorities need to look at."
Newcastle face Chelsea on Saturday as they look to haul themselves away from the relegation zone in the Premier League.
