Ryu became the third player this year to rise to No. 1 in the Rolex Women’s World Golf Ranking
Beats Daniel Berger to complete wire-to-wire victory.
4-under 66 keeps him one shot ahead of Boo Weekley.
Reed, Merritt chasing 23-year-old Texan; McIlroy just makes cut.
The golfer's admission comes three weeks after he was arrested in Florida on suspicion of DUI.
Will be fourth appearance at event for LPGA's most popular player.
Finds stardom at Erin Hills by tying Mcllroy's record of 16-under-par.
Tournament loaded with low scores as several have shot at first major win.
No player in top 18 after play Friday has ever won a major.
Wisconsin's Erin Hills makes its debut as host course.