Japan's Shingo Katayama and Alex Cejka of Germany have withdrawn from the USPGA Championship because of injury.
Katayama, ranked 52 in the world, was forced to pull out because of a recurring back problem.
The 35-year-old finished in a tie for fourth at the 2001 USPGA Championship at Atlanta Athletic Club.
Cejka, meanwhile, has been laid low by an arm complaint and will also miss the season's final major at Oakland Hills in Michigan.
American duo Michael Allen and Tom Pernice Jr have replaced the duo, with the absence of Katayama and Cejka meaning that 93 of the world's top 100 will now be competing this week.

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