World number one Dustin Johnson withdrew from the Masters just moments before he was due to start his first round at Augusta National on Thursday.
Johnson looked set to tee off shortly after 2pm local time despite the back injury he suffered in a "serious fall" in his rented house on Wednesday afternoon.
However, the US Open champion then left the first tee and headed into the clubhouse, leaving Bubba Watson and Jimmy Walker to tee off in the final group.
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Johnson had earlier gone through a short initial warm-up on the range before receiving treatment, the 32-year-old then returning to the range and appearing more at ease as he hit shots under the watchful eye of coach Butch Harmon.