Louis Oosthuizen withdrew in the middle of his first round Thursday at the Tour Championship citing a hamstring injury, according to officials.
The South African, No. 29 in the FedEx Cup standings, is in the midst of a busy fall schedule that will see him travel the globe as he attempts to fit in eight or nine tournaments in a 14-week stretch.
Oosthuizen had come into the Deutsche Bank Championship rested, but earlier on Thursday he had gone to the hospital for a procedure on his wrist.
Beware the injured golfer.