Newcastle boss Alan Pardew says referee Mike Dean has admitted he should have sent off Chelsea defender David Luiz during Saturday's match on Tyneside.
Luiz saw yellow for a professional foul on Demba Ba early on in the Blues 3-0 win at the Sports Direct Arena.
Pardew revealed on Sky Sports' Goals on Sunday that Dean had initially stood by his decision but has since changed his opinion after reviewing the incident.
"He said, 'I made a mistake, he should have been sent off'," said Pardew.
The Newcastle boss added: "At half-time yesterday, his opinion was different, but his opinion would have been altered if his assistant referee had done his job, in my opinion.
"When I saw the referee at half-time, I said, 'Why did you not send him off?'. He said to me, 'He didn't have control of the ball'.
"Well, how can you have control of the ball when the guy is knocking you over?
"I have got no problem with the referee, he made a mistake. The bigger problem I have got is with the linesman on this occasion, because I was looking at the linesman.
"The linesman can see that - he didn't flag, he didn't go mad, he didn't do anything, so Mike Dean is making that decision from 40 yards away.
"If the linesman is waving his flag and suggesting, 'You know what, this is an incident here', and they have got their little mics...
"It would have altered the game, down to 10 men, Chelsea, the pressure they were under.
"I wouldn't have lost my centre-half [Steven Taylor] to injury because we were forcing the game. I had people charging around trying to get back a situation when we would have been in control of the game.
"Not only do I lose the game, but I have lost two players through injury [Taylor and Fabricio Coloccini]. I'm still angry."
The incident occurred four minutes into Saturday's match at the Sports Direct Arena, with the score still 0-0.
Home striker Ba got himself goal side of Luiz, with no other defenders in front of him, but was hauled down by the Brazilian centre-back, who was booked for the foul.
With a full compliment of players, Chelsea went on to win 3-0 through goals from Didier Drogba, substitute Salomon Kalou and Daniel Sturridge.