Sydney: World No. 1,494 Cameron Davis shot a stunning seven-under-par 64 to win the Australian Open by a stroke on Sunday after compatriot and overnight leader Jason Day’s title charge ended in a mid-round collapse.

The 22-year-old Australian holed out for an eagle from the fairway at the 12th and sank an eight foot putt for his sixth birdie at the 18th to finish on 11-under-par, a shot ahead of 2015 champion Matt Jones (68) and Swede Jonas Blixt (68).

Former world No. 1 Day started the day with a one-stroke lead but a double bogey at the ninth after he found sand and water effectively ended his hopes of a maiden title at his home open. He finished fifth on eight-under after a 73.