Queens Park Rangers boss Mark Hughes insists that Premier League managers are "losing faith in referees" after his side were controversially beaten at Manchester United.
QPR's Shaun Derry was sent off after conceding a penalty in which Ashley Young appeared to be offside and have gone down after minimal contact in a collision with the defender.
The incident came a day after Roberto Martinez complained about the officials after Wigan's late 2-1 defeat at Chelsea in which the Londoners survived two debatable offside calls.
Hughes said: "You worry more about decisions going against you and it shouldn't be like that. You should have confidence that the referee will get the key decisions right.
"Just lately a lot of managers have lost faith in them. It is a difficult job. You have to be strong and really clear. You have to be 100% right to give the decisions.
"At the moment people are guessing and hoping that they get it correct. That was the case today."
QPR are 17th in the table and only above the relegation zone on goal difference.
