Andre Villas-Boas has made a formal complaint to referees' chief Mike Riley over the performance of the match officials in Chelsea's 3-1 defeat to Manchester United.
The Chelsea manager was fuming on Sunday after United's first two goals were given despite Chris Smalling and Nani both being offside before scoring.
While he was particularly upset with the assistant linesman, he also wasn't happy that referee Phil Dowd awarded a penalty for Jose Bosingwa's challenge on Nani although Wayne Rooney missed the spot kick.
Villas-Boas has contacted Riley, the general manager of Professional Game Match Officials, and said today: "I was unhappy with the poor performance of the referees which had a decisive role in the result. I don't take it very lightly because those two goals play an important part and you expect the linesman to his job.
"I have already gone further ahead by speaking to the correct people, but I don't want to say what was said publicly. We all feel very down when the ref has such an impact on the result."
Meanwhile, Villas-Boas insists Frank Lampard still has a massive role to play at Chelsea. The midfielder, 33, was taken off at half-time when the team were trailing 3-0 at Old Trafford.
Lampard's future with the England team has already been brought into question after he was left out of the starting line-up against Bulgaria this month.
But Villas-Boas said: "Players of his dimension don't have to prove anything to anybody. The decision I made was tactical. It was not because he was playing badly."
