Bjorn is No. 23 in the world. He was the 54-hole leader at the BMW PGA Championship in England two weeks ago, then faded to finish two strokes behind winner Rory McIlroy. Bjorn cited neck and shoulder injuries. He was replaced in the field by Andrew Dorn, an amateur from the Springfield, Ohio, sectional.
Sterne said he is recovering from an undisclosed injury. He was exempt through the world ranking. Sterne was replaced by Scott Langley, the first alternate from the sectional qualifying site in Memphis, Tennessee.
The U.S. Open is June 12-15 at Pinehurst No. 2.