Jason Day's confident his back is at full strength for the Tour Championship.
The world number one heads into tomorrow's event in Atlanta, fourth on the FedEx Cup standings, but a win at East Lake would be good enough for him to snatch the $10 million bonus.
Despite pulling outof the final round of the BMW Championship with a sore back, Day says he's fully fit and it won't effect his play.
He says he's never hurt his back actually swinging a club, but rather from small mundane tasks in life.
American Dustin Johnson leads the FedEx Cup standings with compatriot Patrick Reed second and Australian Adam Scott third.
