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LANCASTER, Pennsylvania (Reuters) - Amy Yang made four successive birdies on the back nine to claim a three-stroke lead at Friday's halfway mark of the U.S. Women's Open at Lancaster Country Club.
South Korea's Yang added a sparkling four-under 66 to her opening 67 for a seven-under-par total of 133.
The 25-year-old Yang, the Open runner-up in 2012 who was tied for first after 54 holes last year, began zeroing in with her irons, taking dead aim at the flags and sinking four successive birdie putts from the 11th hole.