Back injury forces Will Zalatoris to withdraw from Tour Championship

Will Zalatoris tees off. (Curtis Compton/Atlanta Journal-Constitution via AP)

World number nine Will Zalatoris has withdrawn from the Tour Championship and next month's Presidents Cup due to a back injury.

Zalatoris had led the FedEx Cup standings following his first PGA Tour win in the opening play-off event, but injured his back in the third round of the BMW Championship and was forced to withdraw.