Victor Obinna and Judas Moseamedi fired the Citizens to a third consecutive victory over their local rivals at the Cape Town Stadium.
McCarthy was animated for large parts of the game and after foul by Isaac Nhlapo on substitute Teko Modise right in front of the City bench in the second half, the former Bafana Bafana international was caught on camera appearing to swear at the Urban Warriors defender.
Speaking to the media after the game, McCarthy admitted he over-stepped the mark, saying: “There were a couple of nasty incidents where I think I also over-reacted a bit.
“But I’m one of those guys. I always say a team is a reflection of its manager. I’m a passionate guy from Cape Town, and if people want to bully my players, I’m the first one to stand up for them.
“That was one of the situations where, as a coach, you’ve got to deal with it a little bit better, but it just shows the passion that I have for my players and for the team.”
Modise has battled with injuries and only just recovered in time for the match, which added to McCarthy’s angry outburst.
“I was concerned, as we had worked so hard to get Teko back, and we know he is agile and has trickery, so for players to come in and think they can use him as a kicking bag, I took it a very badly,” the 39-year-old added.
“In the heat of the moment it happens, but I should have been the better person in that incident.”