By Mark Lamport-Stokes
(Reuters) - It has been 14 years since Tiger Woods won the PGA Championship when it was last held at Valhalla Golf Club in Kentucky but the memories of his epic battle with Bob May over the closing stretch remain sharply etched in his mind.
Woods and American journeyman May matched one another shot for shot in a thrilling duel on the back nine before Woods clinched his fifth major title, and third in a row, in a three-hole playoff.
"At the time, I was going on all cylinders," Woods, whose participation in the PGA Championship starting on Thursday at Valhalla is in doubt due to a back injury, recalled of his superb form in 2000.
He triumphed nine times on the PGA Tour that season, including wins at the U.S. Open by a staggering 15 strokes and at the British Open by eight.
"That year, I was really playing well, and it was just a matter of staying out in front. I had the lead going into Sunday (at Valhalla), I had a one-shot lead and I didn't play the front nine as well as I liked.
"I had a couple of mistakes, he played well and then we both got hot on the back nine. It's not too often you're tied for the lead of a major championship and you go out and shoot 31 on the back nine and lose. Unfortunately for Bob that's what happened."
Woods trailed May by one shot through most of a tense back nine on a sultry Sunday afternoon at Valhalla until he birdied the 17th after sticking his approach shot within four feet.
Both players birdied the 18th hole with dramatic, downhill putts to finish the regulation 72 holes with 270 totals.
Woods sank a testing, five-footer to stay alive after May barely touched a double-breaking, 15-footer that dropped into the right edge of the cup to put the pressure right back on the world number one.
Woods closed with a five-under-par 67 while May did one better as he closed a third successive 66.
"He played really well," said Woods, who went on to beat May by one stroke in their three-hole playoff. "There were a couple of turning points, I think, on that back nine for me.
"I made a huge up-and-down on 11. He made a big bomb but I made a sweet up-and-down there. He stuffed in at 12, and I hit a shot up there that's about 15 feet, and I made that.
"That right there was probably a two, three-shot swing on those two holes where I kept myself right in the tournament. Then he missed a big putt at 15 ... again, I made a huge putt to keep it at a one-shot deficit."
Woods fancied his chances of making further headway on the last two holes at Valhalla, the uphill par-four 17th and the par-five 18th.
"I figured, 'Hey, I've got a par-five to play still that I can reach with an iron, and a good drive down 17, and I've got a wedge in my hand'," he said.
"Those are two really legit birdie opportunities. I can still force this into a playoff or win it outright. That was my mindset. Bob made a hell of a two-putt there at 18, and I made a nice little putt myself."
May, who won the European Tour's British Masters in 1999, had been widely expected to flourish as a professional golfer after running Woods so close at Valhalla but his career has since been severely hampered by ongoing back injuries.
He has never won on the PGA Tour, though he has finished second on three occasions -- at the 2000 PGA Championship, the 2000 FedEx St. Jude Classic and the 2006 B.C. Open.
The PGA Championship triumph, meanwhile, gave Woods three majors in a row and enabled him to complete what his 'Tiger Slam' by winning the 2001 Masters to hold all four major titles.
"People forget he had some back issues," Woods, a 14-times major champion, said of his fellow Californian. "I believe he had back surgery, and he went through a really rough period of time physically.
"It happens. It happens in our sport more than people might think. You have your weeks, you have your years. Unfortunately, some players have major injuries that take them right out of their careers."
Woods has suffered his share of injuries over the years, most notably four knee surgeries and also a procedure in late March to treat a pinched nerve in his back.
Since then Woods has played in only three events on the PGA Tour, withdrawing in the middle of the final round of the Bridgestone Invitational on Sunday due to back spasms that cast doubts on his ending a major titles drought that dates back to the 2008 U.S. Open this time at Valhalla.
(Reporting by Mark Lamport-Stokes; Editing by Frank Pingue and Larry Fine)