Kohler - Canada's Graham DeLaet has withdrawn from the 97th PGA Championship because of a left thumb injury, tournament officials announced on Monday.
DeLaet suffered the injury at the Canadian Open last month and missed last week's World Golf Championships event as a result.
"So disappointed that I can't tee it up at the PGA," DeLaet said in a Twitter posting. "Need some time for my body to heal. I plan on being back and ready for a playoff run."
The season-ending PGA Tour playoffs begin two weeks after the year's final major tournament, which begins on Thursday at Whistling Straits.
DeLaet pulling out opened the door for American Sean O'Hair to enter the field. It will be O'Hair's first major start since the 2012 PGA Championship and his ninth appearance in the event, his most at any major.
O'Hair last won at the 2011 Canadian Open although he was in a playoff last March at the Valspar Championship but lost to reigning Masters and US Open champion Jordan Spieth.