Led the US Women's Open after a superb opening 64 in June and shared the halfway pace with Minjee Lee by adding a 69.
However, it was Lee who went three clear in the third round and finished four clear of the Californian, for whom second place represented easily her best performance in a major championship so far.
The daughter of Japanese parents, who run a sushi restaurant, she played in the Junior Ryder Cup, Junior Solheim Cup and Curtis Cup before turning professional in 2009.
Instantly became leading money-winner on the LPGA’s Futures Tour following three wins, but it was not until last season that she had her first runner-up finish on the main circuit and was a Solheim Cup wild card selection.