Hadley birdied his final two holes to edge out Lee who was also chasing his first victory on the PGA Tour.
The 26 year old Hadley, a rookie on the PGA Tour, was a two time winner on the Web.Com Tour in 2013 those victories including the Tour Championship.
Lee recorded just his second career PGA Tour top ten and after missing his last seven cuts this season has found a way to earn US$350,000 and advance his cause as he chases security on the PGA Tour.
Lee, the 2008 US Amateur Champion, became the youngest player to win a European Tour event when as an amateur he won the 2009 Johnnie Walker Classic in Perth but to date he has yet to confirm, on the PGA Tour at least, his undoubted ability. This goes some way towards just that.
Ben Martin finished alone in third position.
The leading Australian and one of only two to make the cut this week was Steve Bowditch who finished 37th.
Tournament invite, West Australian Brady Watt, finished 49th while Brisbane's Bronson La Cassie was 58th.
For Watt who led the amateurs at the Australian Open last December, it was his first cheque in a four round professional event, having missed the cut in events in Thailand and South Africa.