Long, who had missed the cut in three of his first four starts on the PGA Tour leading into this week, had given little evidence that such a significant win was close at hand but playing in the final group today he well and truly boxed above his weight when playing with Mickelson and Hadwin.
A final round of 65 included a 12 foot curling birdie putt at the last to break clear of the three way tie he shared with his playing partners playing the 72nd hole.
For Long, who has battled away on mini and secondary tours for most of his professional career, today's victory and the riches and exemptions it brings is nothing short of life changing.
Not only is the US$1.06 million first prize likely more than he has won in his career to date but he is now exempt for events such as The Masters, the Players Championship and the PGA and will race up the world ranking from his current 417th to just inside the top 130.
Mickelson and Hadwin tied for second place with Talor Gooch finishing 4th one shot further back.
Aaron Baddeley finished as the leading Australian when he shared 18th position following a final round of 65 at the Stadium Course.
Cameron Davis was 28th while Curtis Luck, who began the week so impressively, faded over the weekend to finish 70th.
The PGA Tour now moves to Southern California and San Diego where it will play the Farmers Insurance Open at Torrey Pines where Jason Day will defend his title.
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