Newcastle United manager Alan Pardew was left fuming at referee Mike Dean for not sending off Chelsea defender David Luiz during the Blues' 3-0 win at the Sports Direct Arena.
The Brazilian, who was the last man, brought down Demba Ba in the opening minutes with the score still goalless.
"I am going to have to look at the rule book," said Pardew. "It's a sending-off, it's as simple as that. It changed the game. He's in on goal and he brings him down. I do not understand the logic of referees when that happens. I genuinely believe that the referee got that wrong."
The Magpies saw a contentious refereeing decision go their way last weekend when they were awarded a penalty to earn a 1-1 draw at Manchester United.