The Highland club – who failed to win a match in their first ten league games – will contest the last five matches in the top six after the split for the first time since 2016.
While Mackay has done a monumental job in Dingwall, he was quick to sing the praises of long-term owner MacGregor, who was emotional when speaking to the players in away dressing-room after the victory.
“Today I’m really delighted for our chairman, Roy MacGregor,” said Mackay.
“He got a little bit emotional with the players, which is something he doesn’t do and I’ve never seen before.
“Both for him and Steven Ferguson, who run the football club with a very small staff, I’m so happy for them.
“When a playing staff, football staff and commercial staff and fans all pull together and push in the one direction, good things can happen. It has today.
“I asked him [MacGregor] to come in. It’s not something he would normally do. It’s not an overly emotional person but what I know is that he’s an incredibly passionate football fan and he cares deeply about that club.
“I think the stability at our football club, the fact he’s been there as a constant over the last 20 years, that the club have been in the top-flight nine of the last 10 years when there’s four or five thousand people who live in Dingwall, that the books have to be balanced – i’s great testament to him.
“I’m delighted for him more than anything. He came in and had a little moment or two with the players which was important for me, to be honest with you.”
Mackay also praised the character of his players to recover from a tough start to the season.
“Despite how we were doing, and how well we were playing, we got three points from 10 games and everybody tipped us for relegation,” he added.
“The fact that from then, we have been consistent and gradually climbed up the table, shows great character and spirit from the players.”