Brayan Leon opened the scoring at the Mbombela Stadium from the penalty spot after just seven minutes.
Victor Letsoalo levelled with his goal on 33 minutes, and Sundowns found themselves a goaldown after an unfortunate own-goal by Ronwen Willians, before a late brace from Mkhulise (88', 90+4') after he came off the bench in the second half.
Reflecting on the result, as Sundowns kicked off their league campaign with all three points, Cardoso lauded Mkhulise for his heroics.
The Downs boss told SuperSport: "I think he deserved to the Man of the Match today.
"Sorry by all the work Letsoalo did but I think today, the Man of the Match would very deservedly be Mkhulise by what he means for the club for us.
"He's a player with a fantastic character because he's able to sustain the aggression despite sometimes not being called.
"But we know we have a brother, we have a friend, we have someone that has quality and when we bring him we know what to expect.
“Today, he gave us the energy we needed and the goals also. I picked him on my shoulder, I took him in front of the fans, because he deserved to be carried by me because he carried us also towards the result we needed.”
