Maria Sanchez pulled out of the U.S. Open with a shoulder injury . The world No . 3 was a champion at Flushing Meadows in April . She is replaced as third seed by Poland 's Agnieszka Radwanska . Former U.S. No . 1 Mardy Fish to miss the U.S. Open due to visa issues .
Maria Sharapova pulls out of the U.S. Open with a shoulder injury . The world No . 3 was a champion at Flushing Meadows in 2006 . She is replaced as third seed by Poland 's Agnieszka Radwanska . Former U.S. No . 1 Mardy Fish to miss the U.S. Open due to health issues .