Jose Mourinho called Sergio Aguero "a smart Argentinian player" for his part in Marouane Fellaini's Manchester derby dismissal.
Fellaini was shown a straight red card for throwing his head at Sergio Aguero, seconds after his second rash challenge on the striker, in the closing stages of the 0-0 draw.
The late flashpoint came after a drab encounter in which both sides failed to strengthen their respective claims for Champions League qualification.
Mourinho said: "Marouane says it was a red card because he is Marouane, Martin Atkinson told me in his opinion it was a red card but I saw Aguero in the tunnel - no broken nose, no broken head, his face is as nice as always.
"So, I am not so sure. I think if Sergio doesn't go to the floor, for sure it is not a red card. But if Marouane gave him the chance to do that... I don't know.
"I didn't watch but probably I can guess it's a bit of a red card and that it's a bit of a very experienced, smart Argentinian player."
Mourinho's opposite number Pep Guardiola did not want to get drawn into a war of words with his old adversary about the Fellaini-Aguero incident.
The City boss said: "Next question. I'm not going to talk at my press conference about an action that was in the last minutes - it did nothing to change the game - so nothing."