Alan Curtis accused referee Graham Scott of being out of his depth after his 10-man Swansea City side were beaten 4-2 at home by relegation rivals Sunderland.
Kyle Naughton was sent off by Scott in the first half for catching Yann M'Vila with a high boot, while two of Jermain Defoe's three goals looked marginally offside.
Swansea also benefited from a key refereeing decision when Andre Ayew was given a penalty despite appearing to have tripped himself up in the box by kicking the ground.
But Scott – who was called up as a late replacement for Andre Marriner – was still heavily criticised by Curtis after the match.
"He did look out of his depth – it is difficult obviously, but we are talking about the Premier League here," said Curtis.
"I think the appointment of referees is crucial, especially with a game with two teams down the wrong end of the table."
Curtis was particularly unhappy with Scott over Naughton's red card and confirmed Swansea will lodge an appeal against the decision.
"You have only got to look at the video – he has won it cleanly," added the Swansea boss.
"I think that even though we were the beneficiary of a penalty decision ourselves, I think that you look at the other decisions. I don't want to criticise referees, but I just think he got all the major decisions totally wrong.
"It is going to be a slog between now and the end of the season, but sometimes the decisions can take the game away from you.
"When the referee makes the huge decision to send one of our players off, we are then forced to play for the next hour with 10 men. It is very, very difficult these days to play against 11 men.
"When we analyse the game afterwards, the first goal it looks as though it is probably offside, second goal for them is a huge deflection, third one is another offside and of course then you have got the red card as well.
"I would not say it has cost us the game because you never know how it is going to pan out, but it has had a huge bearing on the game."
