Jang strikes another blow for South Korea
The leader from round one, the 25-year-old Jang had started the day five shots ahead of playing partner Annika Sorenstam and American Cristie Kerr, and never looked like faltering.
She finished on 16 under par and was a four shot winner over Gustafson, the Swede who won the championship when it was last played at Birkdale five years ago and made her final day move with a 67.