Tom Kim will not defend his title at next week's Wyndham Championship.
Kim has withdrawn from the event while he nurses a grade 1 tear in his right ankle.
The 21-year-old South Korean sustained the injury last week after stepping off his patio following the first round of The 151st Open Championship. Despite being hobbled, he carded rounds of 68, 68 and 67 to finish T2 for the tournament.
Kim captured his maiden PGA Tour title at the Wyndham Championship last year after finishing with a final-round 61 at Sedgefield Country Club in Greensboro, N.C.
"I am very gutted to not be able to defend my first PGA Tour win," Kim said. "I am still having a hard time with my ankle, so I am getting the treatment I need to heal completely."
Kim resides 14th in the FedExCup standings and 17th in the Official World Golf Ranking.
"We totally understand Tom's decision to be 100 per cent healthy before he plays again," Wyndham Championship executive director Mark Brazil said. "He has a long career ahead of him, and taking care of his body is the right call. We wish him all the best for a quick recovery and a great run in the FedExCup Playoffs."