LOUISVILLE (AFP) ― Tiger Woods was nowhere to be seen Tuesday at the PGA Championship, except for his image on promotional banners, and his status for Thursday’s scheduled start at Valhalla remained uncertain.

Former world number one Woods, a 14-time major champion chasing the record 18 majors won by Jack Nicklaus, suffered a back injury Sunday during his final round at the World Golf Championships event in Akron, Ohio.

Woods, who underwent back surgery March 31 to ease a pinched nerve, returned in late June and missed the cut at a PGA event his foundation owns, then shared 69th, his career worst 72-hole major showing, at last month’s British Open.

Woods has not finished 72 holes in a U.S. event this year without pain, going the distance only at Doral in March with a final-round 78 when he struggled to bend and collect his ball from the cup and grimaced at times after shots.

It’s a far cry from the level Woods played in the 2000 PGA Championship at Valhalla, when he beat Bob May in a playoff to win the third leg of what would be four major titles in a row ― the “Tiger Slam.”

From his record-shattering first major title at the 1997 Masters to his most recent major crown at the 2008 U.S. Open when he limped to a playoff victory over Rocco Mediate, Woods has attracted fans beyond golf devotees to the sport.

“The dominance of Tiger’s play over a 10-year period is unmatched, really, I would have to say and was quite incredible,” said Adam Scott, who in May dethroned idled Woods from the world number one spot.

Since his last major win, Woods has been nagged by a series of injuries to his back, knees and legs.

But if he fails to play this week, it would mark the first time in his career he has missed three majors in a season, having sat out the Masters and U.S. Open this year while recovering from surgery.

Woods, ranked 10th, had not registered with PGA officials by Tuesday afternoon but could still do so just before his Thursday morning tee time and play in the year’s final major.

Woods, who will turn 39 in December, is slated to play the first two rounds alongside five-time major winner Phil Mickelson and Ireland’s Padraig Harrington.

American Shawn Stefani had been atop the alternates list, but qualified for his first PGA Championship late Tuesday when tournament officials announced American David Toms had withdrawn.

That moved American John Huh into position to be the man to enter the field of 156 should Woods withdraw.

The PGA Championship remains listed as Woods’ next event on his website.