Manchester United manager Jose Mourinho said his side's title hopes are "probably" over because referee Michael Oliver failed to award them a penalty in their 2-1 loss to "lucky" Manchester City.
Pep Guardiola's team stretched their lead at the top of the table to 11 points and became the first team to win 14 successive English top-flight games in a single season.
City took the lead their vast superiority deserved when man-of-the-match David Silva hooked home from close range after confusion at a corner on 42 minutes, only for United to be handed a lifeline in first-half stoppage time when poor defending from Nicolas Otamendi and Fabian Delph allowed Marcus Rashford to steal in for a composed finish.
Otamendi made amends nine minutes after the break when Romelu Lukaku - who had a poor game - lashed at a clearance in the area and the City defender pounced on the rebound to score.
Mourinho's post-match focus centred on an incident in the 79th minute, when Ander Herrera went down in the box under a challenge from Otamendi and was booked for diving.
"My first reaction is I feel sorry for Michael Oliver because he had a very good match but unfortunately he made an important mistake," Mourinho told BBC Match of the Day.
"The result was made with a big penalty not given. That would have been 2-2.
"Michael was unlucky because it was a clear penalty."
Asked whether the title race was over, Mourinho replied: "Probably, yes. Manchester City are a very good team and they are protected by the luck, and the gods of football are behind them."