New Zealander Lydia Ko dropped six shots in the final three holes to finish with a share of 39th place at the US Open in Wisconson on Monday (NZT).
She carded a disappointing three-over par final round 75 for a 12-over total at the testing Blackwolf Run course.
If Ko had parred her way in from the 16th, she would have finished in a share of 18th place, but she faded in the run in, ending her day with a triple bogey at the last.
Ranked No.1 in the world, Ko led the amateur ranks in finishing one shot ahead of American Emma Tally.
The 15-year-old Aucklander says she's learned a lot from playing with the world's top professionals.
"I think playing different kinds of shots, and managing stress and coping with stress - those are just experiences playing with the pros," she said.
Ko remains in the States to play in the US Amateur in Cleveland, Ohio, beginning on August 6.
She'll also have a chance to better her US Open result at the British Open at Royal Liverpool from September 13-16.