Jordan Thompson downs Casper Ruud to win maiden ATP crown at Los Cabos Open
Thompson - who had knocked out top seed Alexander Zverev in a marathon semi-final battle that finished in the early hours of Saturday morning - once again dug deep to overcome fourth-seeded Ruud.
The Australian showed no sign of fatigue from Friday's marathon three-hour, 40-minute battle with Zverev as he took control of Saturday's final with the three-time Grand Slam finalist from Norway.
"It's been an incredible week," said Thompson, who had also saved three match points to recover from 6-0, 3-0 down in a quarter-final win over Alex Michelsen earlier in the tournament.
"I spent some serious hours on the court this week, and I want to thank everyone for staying up late last night and throughout the week. The crowd was amazing.
"It's been a journey. I'm nearly 30 and I'm lifting a trophy; I never thought I would do that."
Thompson broke Ruud in the sixth game of the opening set for a 4-2 lead and then fought off two break points to hold and win the first set 6-3.
He looked to be poised for a brisk victory after breaking Ruud and then holding to go 5-3 up in the second set.
But Thompson appeared to tighten when serving for the match at 5-4 as Ruud took a 0-40 lead to break back and level it at 5-5.
The next two games went with serve to set up a tie-break as the tension mounted.
Yet Thompson regained his composure in the tie-break, taking a 3-2 lead after Ruud double-faulted, and then opening up a commanding 5-2 lead.
Ruud held to get it back to 5-4 but Thompson was not to be denied, taking two match points when Ruud lashed a return long.
Thompson then sent down a booming serve that left Ruud flailing and the Australian advanced to the net to bury a winner that clinched a deserved victory.