The Premier League table was unchanged after Manchester City recorded a goalless draw with Manchester United on Thursday.
The two English heavyweights went head to head at the Etihad in what was a relatively uneventful game until the very end.
With time running out, and with Marouane Fellaini currently on a yellow card, the big Belgian fouled Sergio Aguero.
City players were calling for the midfielder to be red-carded but Fellaini made Martin Atkinson’s mind up for him, headbutting the forward.
After the game Mourinho accused Aguero of play-acting to get the Belgian sent off, saying: “Marouane said that it’s a red card because it’s him.
“Martin Atkinson told me that in his opinion it’s a red card.
“But I saw Aguero in the tunnel and no broken nose, no broken head, his face as nice as always, so I’m not so sure.
“If Sergio doesn’t go to the floor, for sure it’s not a red card, but if Marouane gave him the chance to do that, I don’t know.”
City boss Pep Guardiola refused to be drawn on the red card incident and said: “I’m not here to judge what my opponents decide to do.
“I’m not going to talk about what happened in the last minutes, as it didn’t change the game.”
The Citizens remain in fourth following the game, and currently sit on 65 points. United are a place behind with a point less.
Both sides have played 33 matches and both have a game in hand over Liverpool in third on 66 points.
Next up for City is a trip to the north east to take on Premier League strugglers Middlesbrough, while United will play host to Swansea.
