Jason Day withdrew prior to his first-round tee time Thursday at the WGC-Cadillac Championship due to a left thumb injury.
Day, who won the WGC-Accenture Match Play two weeks ago, was set to tee off on No. 10 at Trump National Doral at 11:44 a.m. alongside Phil Mickelson and Rory McIlroy.
"My left thumb was bothering me at the Accenture Match Play Championship and the pain continued here this week," Day said in a statement. "I had an MRI yesterday here in 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.
"I'm sorry to miss the Cadillac Championship. It looks like it's going to be a great event."
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