Smyth finished six shots behind New Yorker Brandon Wu whose final round of 64 saw him win by three over fellow American Christopher Petefish.
Smyth struggled early in his round as he looked to become the 4th Australian to win what is one of the more prestigious events on the US amateur calendar but after falling well off the early pace he rallied late in his round with three consecutive birdies.
Sydney’s Harrison Endycott who was looking to defend the title he won in an outstanding year for him in 2016 was the next best of the Australians when he finished tied for 13th.
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