Lydia Ko has been unable to defend her Swinging Skirts LGPA Classic title in San Francisco, California, finishing tied for sixth.
Ko began the final round tied for eighth but bogeyed four holes in her outward half to slip to a tie for 13th and well adrift of eventual champion Haru Nomara.
Ko bogeyed her opening hole then three more on the difficult San Francisco layout.
She eventually managed to climb to sixth on the leaderboard in her second half of the round, with the help of a birdie on her 12th hole.
Ko finished eight shots behind Nomara, with the Japanese champion claiming her second tournament win this season.