American Corbin Mills won the tournament to secure his second main amateur title with a wire-to-wire effort after opening with a 67 to never relinquish the lead at The Players with closing rounds of 69-68-72 to finish at 12-under-par, a stroke ahead of Curtis Thompson and Patrick Rodgers.
Mills, 21 from Anderson in South Carolina, last week won the US Amateur Public Links title at Bandon Dunes securing the title on the first extra hole over Derek Ernst. The American's world ranking has as a result of his dural wins jumped to 45th position.
Sinnott's efforts were impressive in his first main tour of the US as the Victorian fired rounds of 69-71-72-69 to finish at 7-under-par to be the best of the Australians. His result is off another top-20 finish last week at the Dogwood Invitational in Atlanta.
"I was happy with the way I came back from my starts," said Sinnott, who also secured top-10 finishes at the Mandurah Easter Amateur and the Riversdale Cup this Australian season.
"My ball striking was solid, although I struggled off the tee at times. These events are a challenge as the field is so strong compared to what we play back in Australia. I would say that consistent approach shots and solid putting helped me to stay par or better for this tournament. I'm pleased with the result and are looking forward to next week at the Southern Amateur."
Kalem Richardson started the final day in second position three strokes behind Mills after opening rounds of 68-69-70, but closing bogies over four of the last five holes did damage for the Tasmanian's chances of claiming a major amateur title in the US as he carded a final round 3-over-par, 75.
Cameron Smith had an impressive tournament with a top-20 result with rounds of 69-72-72-71 to finish in a tie for 18th position.
Nathan Holman, winner of the 2011 Riversdale Cup, fired an impressive final round 5-under-par, 67, to jump up the leader board to finish in a tie at 22nd position after earlier rounds of 71-75-73. New Zealander, Ben Campbell, also finished in 22nd position with rounds of 76-66-73-71.
Matt Stieger and Ryan McCarthy finished in a tie for 31st position with Stieger firing rounds of 70-75-73-71 and McCarthy 71-72-71-75.
Brett Drewitt was the last of the Australians to make the cut and carded rounds of 74-71-75-71 to finish in a tie for 39th position.
Two Australians missed the cut with Tarquin MacManus carding rounds of 82-69-77 and Tim Hart recording rounds of 74-77-76.
The Australian contingent will move to play the Southern Amateur starting 12 July at Innisbrook Golf Club
at Palm Harbor, Florida.
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