The pair began the day with a three-shot cushion over the field and waged an intense back and forth battle for much of the round before Pavan ultimately pulled away.
His eventual margin of victory was two shots but that didn’t begin to tell the story of a thrilling final round which saw the pair locked at 20-under standing on the 16th tee.
They got there via very different routes, Harrington fast out of the blocks then trying to hang on while Pavan started nervously but picked up pace as the day went on.
Back to back birdies at 16 and 17 for Pavan were the difference in the end as Harrington, 47-years-old and two years removed from his last European win, could do no better than par.
Early in the round it had looked like the Irishman was the man most likely when he birdied the first to go one ahead then gained another when Pavan dropped a shot at the second.
At the turn Harrington held a commanding three shot lead after three birdies and no bogeys while Pavan was treading water.
Well done @AndreaPavan89. You played great golf down the stretch but also you were an easy and sporting partner to play with it. Make time to enjoy your success.— Padraig Harrington (@padraig_h) August 26, 2018
But the roles reversed on the inward half as Harrington stalled at 200under while Pavan began to claw his way back.
He birdied 10, 12 and 14 to get within one and when Harrington made his first bogey of the day at 15 the pair were all square with three to go.
And that was when Pavan grabbed his opportunity, his iron to the par-3 16th barely carrying the water but leaving a 25-foot putt from the fringe which he promptly holed.
Another birdie at the next all but locked up the victory, an emotional Pavan ecstatic with his performance.
“It's amazing, it's massive,” he said. “I've won four times on the Challenge Tour but it was a long time ago.
“I'll enjoy this one because it's really hard to get and I'll just keep working on the stuff that seems to be working and enjoy the success.
“I'm going back home tomorrow and we're having a second baby, a little girl is coming on Wednesday. We're really excited about that and I can't wait to celebrate with my family.”
For his part Harrington was gracious in defeat, taking the time to tweet his congratulations after the round and wishing Pavan the best.
Jason Scrivener and Adam Bland led home the Australian challenge, both finishing the week 11-under-par and T18.
Nick Cullen and Lucas Herbert finished four shots further back and T44 while Scott Hend, who played alone in the first group of the day, finished equal last at 4-over.
RULES - MEASURING RELIEF AREA:
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