London coach Andre Villas Boas blamed the referee for the loss to Queens Park Rangers.
Referee Chris Foy awarded a penalty to the team led by the Portuguese coach on Sunday and also sent off two players in the first half: Jose Bosingwa and Didier Drogba. As a result, QPR celebrated a 1-0 victory.
"The referee performed poorly - very, very poorly. And it shows in the result," said Villas Boas. "I spoke to him after the match and was very aggressive. I don't care what he thinks about it."
He continued: "This season, three referees have already had a direct impact on the final result. I think that's way too much. Tonight the referee made a few correct decisions, but in many situations, he made mistakes.
We are fighting for the first place, we want to do it by playing attacking football, but we face referees who have a bad day. I am disappointed because this does not meet the standards of the Premier League."
Chelsea currently has 19 points and is in third place in the league standings.
Images from the QPR - Chelsea match: