Inverness interim manager Neil McCann could not have been more proud of his players after they sealed Scottish Cup progress against Ross County.
It was the first Highland derby in two years, but the Caley Jags had knocked County out of the same competition that season as well after a penalty shoot-out.
McCann was delighted with his side's performance, picking out MacKay's solo strike as a particular highlight.
"I'm delighted; I'm a very, very proud man at the minute," he said.
"This was a tough game tonight. We knew that John (Hughes) might change his shape and might freshen it up a bit. They've got a strong squad, but we were coming in in good form and I think there is a belief about the group in what we're doing at the minute.
"We're hard to break down and score against, but when it's time to attack, I think there's a wee bit of belief about us.
"Daniel is lightning quick and I know speed terrifies defenders and he was one of the ones I wanted to go and show that pace. When he shows it and believes in himself, he's a real handful and a real threat.
"That was a really good individual goal, carrying the ball like he did, cutting inside and then popping it away. I fancied him tonight and told him before the game that I fancied him him to score tonight."
Ross County manager John Hughes was left frustrated with his side's showing at both ends of the park, saying Inverness deserved to go through.
"I thought we dominated the first half without creating any great chances," Hughes said.
"We score the goal, albeit from a set-piece, and it's the story of our season – we can't hold on to it.
"In the second half we lost our way a wee bit, and that's when Inverness came into it.
"If we're giving the goals away that we are – not dealing with balls coming into the box – we're not going to win a game.
"All credit to Inverness, they were the better team in the second half and we never had the quality to break them down. On the second-half performance they deserved to win."