World number 12 Dustin Johnson has withdrawn from the Masters because of a back injury, the American announced on Tuesday.
A five-time winner on the PGA Tour, Johnson will miss the first Major of the year starting at Augusta on Thursday.
Johnson announced the news via his official Twitter account.
"First I have to apologize to the fans and sponsors. With heartfelt regret, I won't be playing in the Masters due to a tweaked back.”
"You have no idea how much I wanted to walk the fairways at Augusta and fulfill (sic) what I've been practicing for!! I'll have to root (for) my buddies!"
Johnson underwent knee surgery in the off-season and has three top-10 finishes to his name on the PGA Tour this year.
The 27-year-old's best result at the Masters was tied for 30th in 2009.
His withdrawal means the field is down to 96 players with the tournament not having an alternate list.