SAN FRANCISCO, JUNE 20 -- A memorable score was shot at Olympic Club in the third round of the U.S. Open today, but not by anyone who started in contention.

With a record-tying 64, Keith Clearwater rocketed ahead of 59 players and moved within a stroke of leader Tom Watson.

Watson maintained the lead he had shared with slumping Mark Wiebe (77) by curling in about a 15-foot putt on the 18th hole for a 71 and 208. A stroke behind were Clearwater and tour grinder Scott Simpson, with Lennie Clements the only other player at even par or better.

The enduring scene on a day when so many shot so high was Tommy Nakajima's shot toward the 18th green that ended up in a tree to the right. A youngster scurried up the tree but failed to find it. Nakajima made double-bogey 6 for a 74 -- 212.

Most of the haggard finishers insisted tour rookie Clearwater played a different course, the greens being softer and more true during his midmorning stroll to glory.

"I was just trying to get in position to possibly have a chance Sunday," the astonished Clearwater admitted. "It's nice to think that, if we play well, yes, we could win the Open."

His 64 tied the competitive-course record at Olympic set by the immortal Rives McBee in the '66 Open; it also matched the 64 Ben Crenshaw shot at Merion in 1981 as the lowest third round for an Open.

"Golf is a very slow game," the clear-thinking Clearwater said. "You can't go jogging down the fairways thinking 64." Still, nobody could imagine a Clearwater shooting close to zero this day and some major-tough players shooting close to infinity.

Jim Thorpe was the first of the leaders to fade, with bogeys on the opening two holes and a triple at the par-4 No. 5. But he rallied with a back-nine 33.

"I didn't know if I was going to finish the day," he said. Instead, his courageous comeback, which included a highlight-film chip to save par at 18, kept Thorpe in contention to be the first black to win a major tournament.

"After the first five or six holes {Sunday}," Thorpe said, "I'm going to take lots of chances. I've got nothing to lose."

Watson dropped three shots in the first four holes, but also pulled himself together nicely. At age 37, he's in the same position he was at age 24: atop the leader board after three rounds of the Open and wondering if he can hold it.

He collapsed at Winged Foot, in 1974, then went on to win eight majors, including the 1982 Open at Pebble Beach, which is not far from here.

"Suffice it to say," he said, "I know how to win. I'd rather be in the lead than behind {because he can afford to make more final-round mistakes}. I've been there before; I will be there again.

"Obviously, I'll be nervous. I'm going to play a round of golf that's maybe the most important of my career. I know that; you're going to write that. How it comes out is anybody's guess."

Players often were hitting shots where forest creatures stray at Olympic. Over here was Wiebe peering from under a tree; over there was Jack Nicklaus (76) hacking from hay.

Still, when asked the player to look for Sunday, Nicklaus boldly said: "Me. I missed nine putts inside eight feet today."

Wiebe's round was as strange as any. Standing on the seventh tee, he was 3 under for the show and had a one-shot lead on the field. Walking off the eighth green, having gone bogey-bogey, he was dropping out of contention.

Soon, Wiebe would drive into unplayable-lie position; later, an equally wild tee shot would draw blood from a customer outside the ropes.

Almost forgotten, in the one burst of brilliance and the half-dozen plunges, was what appeared to be the usually steady par round by Simpson. Appearances also deceive in golf.

"I didn't hit a green or a fairway the first six holes and went 3 over," Simpson related. "I hit every green the rest of the way.

"I thought somebody would be more under par. I thought somebody would be 4 or 5 under, but I'm not complaining."

All of the second-round heroes were in envy of the recently awesome Clearwater, back there in the clubhouse. Or the interview tent. Or the practice tee. Celebrating that sweet 64.

What did it for Clearwater was hitting all but three of Olympic's narrow fairways and making nearly every putt that mattered. Those four off-the-green saves were as important as his six birdies.

Starting at 5 over, Clearwater hit his first shot of the third round crooked, into the rough. From there, he scrambled to a two-putt par on a par-5 considered a birdie hole.

He also managed a chip-and-putt save on No. 2, then hit birdie stride two holes later. After a six-foot birdie at the 438-yard No. 4, Clearwater began a stretch of seven holes in which his birdie effort was never worse than a 25-foot putt.

This was in contrast to the second-round leaders, Watson and Wiebe, Nicklaus, Bernhard Langer, Thorpe and the others. After the first hole, none of those guys could make a birdie until Wiebe's 12-footer at No. 5.

Clearwater, meanwhile, had drained a 10-footer for birdie at No. 8, a six-footer for birdie at No. 9 and a 20-footer for birdie at No. 11, after a 4-iron approach from the rough.

This was wonderful, Clearwater reminded himself, but he'd been in a similar position about the same point the day before -- and faded.

"Two under after 10," he recalled, "and ended up at {1-over} 71. What you have to do is position the ball well enough to allow things to happen."

Which is exactly what Clearwater continued to do. Sort of. For three holes, his chipper and putter saved him from bogey disaster. Off the green each time with his approaches, he finessed pars.

Feeling exhilarated, Clearwater stepped to the 16th tee and hauled out a club he had not used the entire round: his driver. Pleased so well by the result, he used it again on his second shot, from the fairway.

All that remained after that beauty, on the 609-yard hole, was a sand wedge to 12 feet and another smooth tap with the putter for birdie. Naturally, he then birdieied the hole almost everyone else believes is close to impossible to par -- the 17th.

All it took was his best shot of the round, a 3-iron approach that left an eight-footer for his sixth and final birdie of the day.

Clearwater has yet to hit an Open shot under Open pressure. There is considerable difference between stroking the ball in relative privacy, and with the entire golf world watching.