World number 10 Tiger Woods has been forced to abandon midway through the final round of the WGC-Bridgestone Invitational after sustaining a back injury.
The 38-year-old appeared to aggravate his back during his tee shot on the ninth hole at Akron in Ohio, forcing him to pull out of the tournament.
The American missed three months earlier this year after undergoing back surgery, but said that he has not had any problems since making his return in June.
Woods was the defending champion at the event.