Leona Maguire sensationally captured her third title of the season to send Duke in the NCAA finals and edge closer to becoming world No 1.
The Slieve Russell star, 19, closed with a level par 72 on the Warren Course in the NCAA South Bend Regional to edge out team mate Celine Boutier (74) by a stroke in four under par 212.
Twin sister Lisa finished tied 76th after a 76 as Duke took the team win by three strokes from Wake Forest to lead the six colleges that progressed to the NCAA finals at the Concession in Florida from May 22-27.
Currently at No 2 in the world. Leona Maguire is the top-ranked college golfer in the US and on course for a recording a record breaking season.
Before this week she had a 70.68 stroke average — on pace for a Duke record — and including this week has now posted 22 rounds of par or better.
She now has three wins, seven top fives and eight top 10s and looks on course to replace American teenager Andrea Lee at the top of the World Amateur Golf Ranking.
Lee, who has verbally committed to attend Stanford University in 2016, finished tied 51st in the Swinging Skirts LPGA Classic on April 26 in her most recent start.