The Swede sent home a powerful free kick in the first half before adding a dramatic winner in the 87th minute to hand Mourinho his first major honour at Old Trafford.
Triumph over Claude Puel’s side ensured that Mourinho joined Sir Alex Ferguson and Brian Clough in the list of managers with four League Cup wins.
And Zlatan, speaking after the game, was quick to label the 54-year-old as a born winner.
“I got a call from Jose Mourinho — I might have a good relationship with him — and, when he called, that’s the reason I came,” he said. “I’m happy I came. I know I made the right choice. I predicted things — what I predicted is what I’m doing now.
“He is a winner. When you get Jose you know what you get. If you want to win, you get Jose and that is the way it works.
“The club knew what they were doing when they bring him, it is nothing new, it is something that keeps going and following him, I’m super happy for him.”
Mourinho would have felt an enormous wave of relief wash over him when that Zlatan header flew past Fraser Forster. After the tumult of his failed spell at Chelsea he needed to make a statement, to remind the footballing world of his capacity to deliver in big moments.
But for all the joy that came with United’s first major trophy of the Mourinho era, you could sense that the Portuguese’s overriding emotion was one of disappointment. The 54-year-old sets rigid standards for himself and his players, and Sunday’s performance, whilst ultimately victorious, did not align with what he expects from this side.
He will always demand more; he will always look to the next possible triumph. And that, above anything, is why the managerial hot-seat at Old Trafford suits him so well.