McCarthy had to miss the match because of a bug which kept him away from the training ground all week.
In his absence Tommy Smith scored two, and there was one apiece by strikers David McGoldrick and Aaron Mclean in an emphatic win.
"Mick's absolutely delighted with the result and performance," said Connor. "I spoke to him straight after the game.
"He's been really struggling for two or three days and he's just beginning to get over it. He wanted to get in today but every time he stands up he feels weak and very tired.
"It's the first game of his managerial career that he's had to miss his team playing, so I'm pleased we got the result for him. Hopefully it'll make him feel a lot better.
"He can come back to work on Monday knowing we won 4-0, got three points and kept a clean sheet."
"After our second goal we blossomed and grew in confidence and belief. The two goals were a bit of payback for Tommy, for all the times he's been in there and nearly scored, when the flight of the ball has just beaten him.
"You have to keep persevering and this week he managed to score two superb headed goals."