Katayama: Withdrawn
An upper back injury has forced Shingo Katayama to withdraw from the US Open.
The Japanese player is the fourth competitor - and the third ranked in the world's top 50 - to drop out of the major championship, which begins on Thursday at Bethpage Black.
Katayama, who was fourth in April at the Masters and is ranked 39th in the world, will be replaced by 19-year-old American David Erby in the 156-man field.
Others who have previously pulled out are Sweden's 14th-ranked Robert Karlsson, the 2008 European Order of Merit champion who has an eye infection, South Africa's 45th-ranked Trevor Immelman, the 2008 Masters winner who has left wrist tendinitis, and American Dudley Hart.
Teenager Erby is the 16th amateur in the event.

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