Walker, 35, is ranked second in the standings behind Rory McIlroy. He recently spent time at home recovering from minor surgery rather than getting ready for the playoffs.
The New York Times' Zach Schonbrun wrote about Walker's other on-course challenge:
Walker has a new mission, though. It is about protection and awareness, and for a fair-skinned Oklahoman with a family history of skin cancer, those elements are essential.
“I watched what Aron Price went through, and he had melanoma, and that was bad, really, really, scary bad,” Walker said after his even-par round. “He had that removed and he’s doing great, but we’ve all got to be diligent about what we wear. The sun will kill you.”
Price, an Australian golfer, developed the disease in different spots on his shoulder in 2011. Likewise, Walker said, he had a spot on his lip removed in 2004. That served as a reality check, and he said he thought he had been conscientious about wearing skin protection since then.
Apparently it was not enough. During the Bridgestone Invitational this month, a biopsy on a nodule just below his left eye returned positive for basal cell carcinoma, requiring minor surgery Aug. 11.Walker said it's a genetics thing.
His sunscreen mantra? Reapply, reapply, reapply.