Swansea manager Garry Monk says referee Mike Dean should not have awarded Crystal Palace a late penalty at the Liberty Stadium.
Swansea had to settle for a 1-1 draw after a late penalty by Glenn Murray rescued a point for Crystal Palace.
Murray beat Swans goalkeeper Michel Vorm to the ball and was fouled by Chico Flores, who was sent off, on the edge of the penalty box.
"On the TV replays and everything it is clearly outside the area," said Monk.
The Swansea head coach, who replaced Michael Laudrup, criticised how match referee Dean could have award the 80th penalty.
"The referee for some reason has made a decision from 60 yards away, he was further away from the ball than I was," said Monk.
"How he made that decision, I looked straight at him funny enough and he never conferred with his official on the other side.
"He had made the decision himself, its quite bizarre...and we end up getting a man sent off.
"It's not a penalty, it's one against us and that obviously gave them the equaliser."
Monk, who has now won one of his five games in charge, admitted he was frustrated at the approach of Palace and claimed they came to south Wales looking for a draw.
"Crystal Palace came here organised and played very deep," said Monk.
"They weren't really looking to win the game and they were probably just trying to dig out a point."
Midfielder Jonathan de Guzman gave the Swans a 1-0 lead after 25 minutes after a slick passing move as the hosts dominated.
But with eight minutes left, Murray won Palace their penalty and scored from the spot and though Palace pressed for a winner, the 10-man Swans held on to take a point.