Bendigo's Andrew Martin slid down the Australian Open leaderboard as Sydney's Matt Jones clung on to win his second title.
Martin went into the weekend at four-under par and in contention for a top-20 finish, but consecutive rounds of 74 saw him drop to a tie for 52nd at two-over par.
He finished 17 shots behind a triumphant Jones, who held off South African star Louis Oosthuizen by one shot.
Jones made a clutch up-and-down par at the last to claim a one-stroke victory on over Oosthuizen, who eagled the 72nd hole to set up a dramatic climax.
Champion in 2015 at The Australian Golf Club, where he's been a member since he was 15, Jones finished at 15-under-par for the tournament after closing with a 69.
Jones looked like winning in a procession before Oosthuizen's late heroics.
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Like a Sunday afternoon stroll in the park, Jones casually walked the fairways hand in hand with his wife, a former Miss Idaho, and seven-year-old daughter Saber as he watched his challengers come and go for most of the day.
But matters turned dicey when Oosthuizen suddenly cut his lead to one and Jones found a bunker off the tee on 18.
Unable to re-find the fairway from the trap, he left his approach 10 metres short and had to hole a five-foot putt to become the 19th multiple winner of the Open - and first since American superstar Jordan Spieth three years ago.
"It's a great honour to be able to put my name on that trophy with all those champions and there are multiple major champions on there," Jones said.
"To be on the trophy with Jack (Nicklaus) and Gary (Player) and Greg (Norman) and Adam (Scott), Rory (McIlroy), Jordan.
"To be able to do it twice is very special and something that I'll be able to look back on later in life and be very proud of."
Victory also earned Jones a British Open start next year at Royal St George's, where Greg Norman won the Claret Jug in 1993 for a second time.
- with AAP
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