"Last time it went out, I changed a diaper" - Jason Day battles back issues ahead of Tour Championship

Day is one of 30 competing in the final PGA Tour event of the year before the Ryder Cup

Jason Day

Image: AJ Mast / AP/Press Association Images

Jason Day is intent on seeing out the PGA Tour season with the final event of the year before the Ryder Cup - the Tour Championship.

The Australian has struggled with back issues during his career and they have flared up once again, most recently at the BMW Championship two weeks ago when he was forced to sit out the final round of action.

The world number one heads into this weekend's 30-man tournament ranked fourth in the standings and in with a shout of becoming the overall Fedex champion.

"It's not the first time it happened," he told ESPN. "I put the tee in the ground at the BMW Championship , and my back went out.

"Last time it went out, I changed a diaper. So it's nothing where I physically make a move at it during a swing and my back goes out. It literally is from the smallest things -- picking up a pillow, picking up something off the ground, or just moving the wrong way."

The 28-year-old has won three times this season, including the WGC-Dell Match Play title, but the busy schedule may have caught up with him physically. Ahead of the tournament, he says he feels back to normal.

"I feel like the practice over the last couple of days back at home felt pretty good,'' he said. "Haven't been able to prep as much as I would like ... but overall I feel good.''