After impressing in recent weeks, Mackay introduced Mutch as a half-time substitute and the youngster made an immediate impact, setting up Peter Odemwingie's goal.
Despite it not being enough to claim a point, Mackay was delighted with the 21-year-old.
"Jordon's a top young talent," Mackay told reporters. "He's only 21-years-old and there's a lot of potential there.
"There's a lot of facets to his game and there's areas that he's improving on all the time.
"He's certainly someone that came on and took the game by the scruff of the neck and showed why he's here. It's about players taking their chance when they get it."
Mutch joined Cardiff from Birmingham City in 2012.