Miami - World number four Jason Day of Australia withdrew from the World Golf Championships Cadillac Championship on Thursday with a sore left thumb.
Day, who won the WGC Match Play crown two weeks ago, pulled out before his late-morning tee time.
"My left thumb was bothering me at the Match Play Championship and the pain continued here this week," Day said in a statement.
"I had an MRI yesterdayn Miami with Dr. Lee Kaplan. Fortunately, the MRI was negative, but the doctor prescribed rest if I was unable to play today. My plan is to rest for a couple of weeks."
The 26-year-old Queenslander had not withdrawn from an event since the 2012 Masters, where he pulled out because of a wrist injury.
Day was among the favorites at Doral, although his best showing at the Blue Monster course was a share of 20th in 2012.