Now, the dank and foggy stage is set for Tom Watson to win the U.S. Open. Today at the Pebble Beach Golf Links, here by the glowering and chilly Pacific, all the ingredients and variables necessary for a Watson victory seemed to fall in place.

At evening of this third Open round, Watson found himself deadlocked for the Open lead with defending British Open champion Bill Rogers, two strokes ahead, at four-under-par 212. Thanks to seven birdies, Watson scalded Pebble for a 68 this afternoon, one shot better than Rogers' five-birdie round.

Just off this pace at 214 is a formidable quartet: defending Open champ David Graham (69), 1981 Open runner-up George Burns (70), fading second-round leader Bruce Devlin and Scott Simpson.

As if this weren't enough power waiting in the wings, Jack Nicklaus (71) is tied with Calvin Peete at 215 while lights-out birdie machines Craig Stadler (70) and Lanny Wadkins (67) are part of a quintet at par 216.

In all, 13 players are within four shots entering Sunday's California gold rush. And six of them have won major championships.

Yet, even in the face of such competition, it's Watson who seems to hold most of those ephemeral advantages which, in golf, lurk between the ears.

Finally, those external fates and internal foibles which have bedeviled him from Winged Foot to Medinah to Southern Hills to Atlanta to Cherry Hills to Baltusrol seem, at last, to have relented.

Or, perhaps, they've just had pity on the gap-toothed redhead with the quick swing and the tight nerves who always tries so hard, perhaps too hard. At all six of those aforementioned beautiful places, with their euphonious names, Watson has finished in the Top 10. But never won.

In his 12th pro season, four times player of the year, Watson stands near the pinnacle of his sport. Yet, he knows, without a U.S. Open to complement his three British Open wins and two Masters triumphs, he can never hope to move into the company of Palmer and Player, Hogan and Hagen, Sarazen and Snead.

First among Watson's advantages is his own gloriously confident, almost cocky, state of mind.

"I have a very good feeling about my swing and I can't wait to get out there to play tomorrow," he said, beaming. "I've had two pretty good chances to win the Open before, at Winged Foot and Medinah. I hope the third time's a charm.

"Sometimes, it only takes one good swing to turn your whole feeling about your game around," said perfectionist Watson, who is almost mystical about the importance of the "feel" of his swing. "Maybe I made that swing today, the three-iron I hit to three feet for a birdie at the (204-yard) 12th. I hadn't hit a shot with that kind of authority all week."

Also, Watson loves Pebble Beach, where he's twice won the Crosby. He's always thrived in chilly seaside weather and he likes a fast-track links style of play. He's delighted that the rough here, which usually chokes his wayward drives in the Open, is relatively merciful; in fact, when he drove into the hay nine times on Friday, he still shot 72.

This place holds few of Watson's familiar Open fears. Even the greens, thanks to damp, misty weather, are less than lightning fast, which allows him to putt aggressively, something he does better than anyone.

Next, Rogers, the cheerful Texarkana pro with the straight drives and the crisp irons, seems in a less than a totally positive state of mind. In fact, Rogers, who limped to the clubhouse this evening with a bogey on the 17th and a miss of an easy four-foot birdie putt at the 18th, talks like a man looking for a soft place to fall.

"I'm close to playing well . . . but I'm not playing like I was at the British Open last year," said Rogers, who made birdies at the par-4 14th and 15th to take the lead alone. "My putting has saved me a lot all week.

"I've learned patience and I'll play off my past successes on Sunday," added Rogers, who was tied with Burns for second at Merion in 1981. "You can't trick yourself into not knowing what's gone before. If I'd blown the British Open last year, it would stay with me. But I didn't. That helps . . . because, no matter what anybody says, the last round of the U.S. Open . . . (pause) . . . It really is genuine pressure."

Watson knows about that final-day pressure. In 1974 and 1975 Watson could, as it turned out, have won a pair of U.S. Opens just by shooting last-round 73s. In fact, he closed with a 79 and a 77, two scores that gave him a "choker" tag it took years to live down.

Another Watson bonus is the glum state of mind of the greatest Sunday Open player in history, Nicklaus. From tee to green, Nicklaus has been in a higher league than Watson, or perhaps anyone else, all week. But, Nicklaus may never have putted more miserably from his favorite range, eight to 15 feet, in his life.

Those makeable putts are a measure of willpower, confidence, and, often, youth. For three days, Nicklaus has found dozens of ways to miss birdie putts by an inch or less. That trend, once begun, is seldom reversed in mid-major.

But, again today, Nicklaus made only one putt longer than a yard, and also missed a 2 1/2-footer he called "the easiest putt of the lot . . .

"I played well enough, again. Though, basically, I didn't get it as close to the hole as I should have. But, I didn't make much, either. Tomorrow, I have to do better if I'm going to win. My position is not bad by any means. Anybody under par has a good shot," said Nicklaus, not bothering to hide his dejection.

"These greens are very hard to read. I've only had 21 years experience on 'em. Someday, I'm going to learn 'em."

Nicklaus was also obviously perturbed that he had made up so little ground on "two easy days . . . with no wind. The course is soft. Sometimes, it plays faster than this at the Crosby."

Translated, this means that Nicklaus wishes the winds would blow the scores to the skies. Then, his iron nerves, his new-improved swing and his diet of two-putt pars might well be good enough to push him ahead of a frightened, overmatched and collapsing field, the prone-to-hook Watson among them.

However, when told more of the same calm weather was forecast, Nicklaus' face dropped. Under these conditions, he knows, Watson's chances of an erratic round are reduced. And his superiority with the putter is increased.

While Nicklaus was finishing his round with a particularly dispiriting succession of marvelous iron shots, followed by agonizingly tentative putts, Watson was banging 10-foot birdie putts into the back of the cup at the 16th and 18th to charge into his tie for the lead.

Actually, most of the field limped into the barn at dusk. Andy North, who was four under par for the tournament after seven holes, was nine over par thereafter, blowing himself off the board with a 77. Local lad Bobby Clampett, tied for the lead on the back nine, bogeyed three of the last four holes to end at 72--216, where he was tied with long Dan Pohl (of Masters playoff fame) and one-day wonder Larry Rinker (75).

The only man who finished with Watson-like panache was Graham, who wants to be the first man since Hogan in 1950-51 to win consecutive titles. Ignored by the crowds, the TV cameras and the leaderboards most of the day, Graham birdied the 16th, then, at the 18th, drained a 35-footer for birdie. "Bingo . . . field goal," he said with a grin, describing his final putt. "Obviously, I've got a chance, don't I?"

Many do.

But, the best chance belongs to Watson. No one knows it better than this great golfer with the zero-for-10 record in his nation's championship.

As he tries to sleep with visions of a place in golf history in his head, Watson's wealth of palpable advantages might turn into his only burden. He must realize that, if not now, when?