"What a Herculean effort," the commentator said as De Minaur claimed a second battling victory in as many days to win his first ATP500 tournament — he won his previous six titles at ATP 250 events, most recently last year at Atlanta.

Having beaten world number 10 Holger Rune in an energy-sapping 2-hour, 48-minute semifinal that had finished at almost 3am the night before, a slow start was  understandable for the 24-year-old Australian.

But Paul too had endured a brutal slog in his semifinal, beating fifth-ranked Taylor Fritz in a match that lasted three hours 25 minutes and badly tired in the final set.

"It feels great, it feels amazing," De Minaur told ATP TV after the match.

"I know the hard work I've put in to be here, and it's good to see the results.

"It's not always that you win a tournament and you get to finish a week unbeaten so I'll definitely cherish this heading into Indian Wells and Miami."

Paul had five break points in the first game of the final set but could not take any of them, with de Minaur then rattling off five-straight games before eventually claiming the final set with a thunderous ace.

"It was huge," de Minaur said of that game in the context of the match.

"Just to kind of stay in the match, especially in the second set [there were] a lot of unforced errors.

"I just dug deep, scrapped my way through it and then the first game of the third set was exactly like my semifinal against Holger [Rune].

"I had that in the back of my mind and I just told myself to keep pushing and if I could keep pushing myself and get out of that game then the momentum is gonna switch so I'm very happy I was able to get out of that."

It was De Minaur's fourth victory out of four against the American, having won all three contests in 2022. 

"Demon played an unbelievable match," Paul said.

"I just respect you so much and I'm happy for you. Congratulations."

The victory sees Alex De Minaur move back into the top 20 to 18, just short of his career high of 15.

"I just want to keep pushing, keep getting the most out of myself," de Minaur said.

"I might not play unbelievable tennis every day but I know I'm gonna fight until the end.

"I've got a whole lot of heart in this little body of mine and I enjoy competing, so very happy with it."