Updated

Defending champion Alexander Noren has withdrawn from the Wales Open because of a back injury after shooting a 10-over 81 in the first round.

Noren had six bogeys, a double-bogey and a quadruple-bogey on a windy day at Celtic Manor on Thursday.

Noren qualified at Walton Heath on Monday for the U.S. Open in San Francisco starting June 14. It's not clear if the injury will rule him out.

Gary Boyd of England has also withdrawn after complaining of dizziness following his round of 87.