Ian Holloway believed Palace should have been awarded a second half penalty in their 1-1 draw with Blackburn.
The Eagles boss thought Glenn Murray was pushed to the ground as he leapt for header inside the Blackburn penalty area mid-way through the second half.
But referee Philip Gibbs failed to point to the spot – and Holloway said it was the wrong decision.
The gaffer said after the match: “Do I need to mention the most blatant shove on anyone I've ever seen? Murray's coming in on it to head it, I don't understand what excuses they've got not to see it.
“If that's not a penalty I don't know what is. I just find it pretty sickening really.”
The result leaves Palace in fifth place in the Championship with two games still to play, although they are now without a win in eight matches.
But the manager was pleased with his team's overall performance at Ewood Park.
Holloway added: “The rest of the game was a good game. Blackburn played their part in a very good game but I thought we were solid, we were in control of things.
“I had to make a couple of changes because they did tactically, but we were very resolute.
“Generally, I'm a bit bemused how we haven't taken all three points.”
To see the gaffer's post-match press conference in full, see Palace Player on Monday.