Nobody scaled golf's mountain more quickly than Johnny Miller; nobody fell to the bottom more swiftly. And when the three-iron shot of his life stopped 15 inches from a tap-in birdie late today his comet-like comeback seemed complete.

Miller seemed fully capable of dominating golf in the '70s. He was THE young lion. But he had missed the cut in half his 16 tournaments this year and was a rabbit-like 106th on the money list before the Colgate Hall of Fame tournament here this week.

He had leaped into our lives in a single round, the 63 that won the U.S. Open six years ago, and he seemed about to re-emerge a winner with almost as much flair. There had been another 63, here Friday -- and when he holed that glorious bird on the 71st hole today he had a one-shot lead on the field.

"Welcome back," somebody from the gallery yelled as Miller walked to the 18th tee.

Miller may well have allowed that thought to creep into his mind about then. And it may well have been costly, for he won a golf tournament and then lost it -- or at least put himself in position to lose a playoff to Tom Watson -- in the space of two swings.

The three-iron shot allowed him to break a tie with Watson; his next tee shot reminded him these returns to the top are not as smooth as one might imagine. There have been wilder hooks from better players, but not many, and his "safe" par all of a sudden was going to require a near-miracle.

"I was all jazzed up after 17," He said. "I tried to hit it too hard. I'd never hooked the ball under pressure before, but I guess I'm just a little bit different than I used to be."

Miller won eight tournaments and $353,021 the year after that Open victory; he was second on the money list the next year, with $226,118, with iron shots that bored holes in the sky and landed close enough to make him appear to be a better putter than he in fact was.

For three years, his decline began, steadily, in increments of about $100,000. In '77, the drop became drastic, and the what's wrong questions became louder and worldwide. Last year he made $17,440 and nearly everyone simply began to forget about Miller. This year some of his exemptions started to run out.

Incredibly, he failed to meet any of the standards for the PGA tournament this year.

"There were two main reasons," said his longtime caddy, Andy Martinez. "Priorities for one. I don't know if golf is No. 1 with Johnny Miller. It's probably behind his family and his church. He's got five kids (the oldest, 9, had an important tournament himself this week) and wants to be near them always.

"Also, there were physical things. Near the end of '76, he bought a ranch. And he worked it, home on the range, and naturally put on weight. Maybe 10 pounds in all, where he didn't need it, in his arms and upper body. In '77, his tempo was destroyed. He was hitting graphite off the tee -- and didn't have a chance.

"In the beginning of '77, he was so bad driving you wouldn't believe it. Now the weight's down and the driving is back. And the putting is coming around (although Miller made but two putts beyond five feet in the final two rounds)."

So his game, the suddenly decent driving, the still-exquisite iron play and respectable putting, came around well enough in recent weeks for him to enter the Hall of Fame tourney with confidence. And to lead it until that duffer hook put him in near-impossible position off the 18th fairway.

He had a swing, but the ball was on pine needles and sand-covered hardpan and the route toward the green was exceedingly narrow, with one dastardly branch 20 yards away hanging expecially low. In addition, Miller could not ground the club for fear the ball would move.

"It could be worse," Miller said when he first saw his ball.

But not much. Martinez explained the dilemma.

"It's 218 yards to the pin, 192 to the front of the green. You gonna fade it or hit straight?"

"Try to hit it super low -- and cut it. That branch is low, man. Wish me luck. Okay, hack, let's see what you can do."

Only relatives of other players were rooting against Miller this week. Warm applause greeted him everywhere; rebel yells pierced the air after an especially solid shot. But this first visit to the rough today became very costly. The two-iron he punched sent the ball too low. It hit a bank about 100 yards away and rolled into the rough, near a bunker 50 yards from the flag.

He pitched to about 35 feet and missed the putt.

If Miller, the unhappy hooker, was frustrated at walking off the 72nd hole and toward a first-tee playoff instead of a first-place check, the fans were delighted. Miller versus Watson, head to head, at last. They had not been paired for the final round, as everyone had hoped, although Miller was a stroke ahead of Watson after three rounds.

At 32, Miller is three years older than Watson. They became prominent during a similar period, Miller for winning 14 tournaments in three years and Watson for late-round folds in major tournaments. Miller decline had corresponded almost exactly with Watson's ascendency. That money record Miller established Watson broke last year.

They greeted each other icily before the playoff and, although he was the defending champion, publicly no one rooted for Watson as they walked the 200 or so yards to the first tee. Once again, to his dismay, Miller learned something new about himself.

"Usually when I'm pumped up, I tend to hit it shorter than normal," he said."This (two-hole) playoff I hit it much farther. I hit a nine-iron 160 yards on the first hole, blanked the flag but it went long and (he got up and down for par).

"The second hole I hit a seven-iron 154 yards. I normally hit a six that distance, but I thought I'd be safe. After Tom hit his iron (40 feet from the flag) I said: 'Baby, this is mine.' But it went long and down a slope. I couldn't wait to get to the third hole, 'cause I knew I'd win it there.

"I birdied it all four rounds, from an average distance of two feet. But the chip on two had to be hit into a slope. A pitch wouldn't have stopped anywhere close. But it just wouldn't go and I missed the 14-footer (for par).

"Usually, I don't blow leads like that. But then I haven't been in this sort of position for a while. I want to take a day or two off, but this has got to help next week. I'm down right now, but at least nobody can say I can't even get in position to win any more."

Miller is back, but the distance between him and Watson still is considerable. At the moment, it is $399,599.