Mings stamped on Zlatan Ibrahimovic's head in a fractious 1-1 draw with United last season.
Ibrahimovic viciously elbowed the defender in the face just minutes later as the two players contested a header in the United penalty area.
And now Mings has revealed in an interview with the Guardian, exactly what the Manchester United manager said to him after the unsavoury incident.
“I didn't recognise up until half-time that it was even a big deal," said Mings.
“Because I hadn't meant to do it, I didn't feel like it would be a talking point.
“But I realised it was when Mourinho came over as we were coming out for the start of the second-half
"He started giving me some abuse, saying: 'You think you're clever. You're going to get an eight-match ban'."
Mings brushed the comment off, but just as the second-half was about to get underway, referee Kevin Friend told him that the incident was likely to be reviewed.
"I said: 'What will get reviewed? He said: The stamp on Ibrahimovic's head'," the Bournemouth defender said.
"I was thinking: 'I don't need you to tell me that just as we're about to start the second-half'.
"And then when I got into the dressing room after the game, someone checked their phone and told me just how big the coverage of the incident was."