Augusta, Ga. ? Justin Rose managed a smile as he walked up to the 18th green, shrugging his shoulders helplessly at what certainly will go down as one of the most wretched days ever at the Masters.

Woods, water, sand, rough — whatever trouble there is at Augusta National, Rose found it Saturday.

All he missed was the Eisenhower Tree.

“I’m still a bit shell-shocked, to be honest,” said Rose, whose 9-over 81 took him from the top of the leaderboard to the middle of the pack. It matched Lee Trevino for the worst third round ever by a 36-hole leader at the Masters and cost him any shot he had at a coveted green jacket.

“Whether you believe me or not, I felt in a great frame of mind going out there,” he said. “I just got off to a bad, bad start. Every little minor mistake got punished, and that’s what Augusta is all about.”

Yes, but this was cataclysmic. Rose, the youngest pro in the field at 23, had been nearly perfect in his first two rounds, making only two bogeys for two-stroke leads each day. Bad drives somehow found the fairway. Ugly shots wound up sitting pretty. Long putts dropped.

Not Saturday. His first tee shot plopped in the bunker, the approach was long and he couldn’t get up-and-down. At No. 2, an errant pitch landed in the first row of fans, leading to another bogey. He made it three bogeys in a row at No. 3 — and the collapse was on.

On No. 9, his 15-footer for birdie skidded about 25 feet past the cup. His comebacker crawled up to the edge of the lip and stopped, giving him six bogeys on the front nine and knocking him back to even par.

“It was tough. My good putts didn’t go in, my good shots didn’t get rewarded,” Rose said. “Every break seemed to go against me today. Yesterday, they would have gone my way.”

It didn’t get any better on the back nine, either. His approach shot on 13 landed in the water, and then his five-foot par putt rolled past the cup. He had a rare chance for a birdie on the 14th, but that putt just missed, too.

On the par-5 15th, Rose’s second shot hit the slope of rough in front of the green and trickled oh-so-slowly down and into the water. As the crowd groaned, Rose fell to his knees and looked at his caddie as if to say, “What is going on?”

Oh, but there was more cruelty to come. He missed a birdie on the par-3 16th when the ball hit the back of the cup and spun off. He finished with nine bogeys and nine pars.

“I tried,” Rose said. “I just really tried to grind it out, but as hard as I tried, I couldn’t turn it around. Which is frustrating, because I felt this was as good a chance as I ever had to win it, the way I was playing.”

Rose did get a little boost from the gallery around the 18th green, which gave him a standing ovation.

“That was actually a nice touch,” he said.

Despite the horrific day, Rose managed to smile and even laugh after his round. He is, after all, only 23. And he already knows more about hard times than most people twice his age.

“I said to someone that no matter what happens, today was going to be a great learning experience,” Rose said. “It’s not the end of the world. But it hurts, because this week I was thinking I was playing well enough to win. So that’s a shame.”