Yahoo Sports reports: Nelly Korda won the US Women's Open on Sunday, rolling in a clutch birdie putt at the 17th hole to break free of a crowded leaderboard and triumph by one stroke at Riviera Country Club.After rolling in the nine-foot birdie at the penultimate hole to seize a slender lead, Korda had one more heart-stopping moment as her three-foot par putt at the last circled the cup before dropping in.