Bobby Clampett walked out of a storybook. Never has a golfing prodigy grown to maturity in a more dream-like setting, and near the spot he frequently used to sneak onto these lustrous links Clampett today made the birdie that would lift him among the first-round contenders in the U.S. Open.

Clampett became addicted to golf the last time the Open was held here, a decade ago, and in his early teens regularly joined pals with access to a car for dozen-hole raids on Pebble. Time and again, they would scurry on near the fifth green, quickly tee it up at six and try to avoid both hazards and marshals. In those daring days, he would play every hole but the first.

And never get caught, Pebble being more relaxed in the mid-'70s and under different management. Clampett was booted off snootier Cyprus Point once, which meant that he simply lugged his clubs perhaps a quarter-mile through some dunes and started playing again on the fourth hole at Spyglass.

"And the time I didn't get kicked off Cyprus," he said, "I birdied 16 (one of the most famous holes in all of golf) in the dark. Never forget it; I hit a driver on the green and made a 30-footer. I was about 15."

Kids in love with golf fantasize what Clampett has lived. At 12, he shagged balls for David Graham and some other pros playing the Open, rode a helicopter to Pebble and once bummed a lift back in a four-door magic carpet with Arnold Palmer.

That's when anyone paying attention should have drawn a career-long bead on Clampett, for any 12-year-old with enough nerve to ask Arnie for more than an autograph is special.

"I walked up to him and said: 'Mr. Palmer, are you going back to Carmel Valley Golf and Country Club?' " said Clampett, his voice assuming preteen pitch and quiver. "And he turned around toward me"--here Clampett tugged at his pants, as Arnie surely had.

" 'Hmmmmm,' " Clampett quoted Palmer. " 'Hey, there son. Yeah. Want a ride?' So I hopped in the car. Mark McCormack, who's now my agent, also was in the car." Clampett dearly wanted every one of his buddies to see him parade by with Palmer, but that never happened. The only one in sight never saw his waving and mugging from Arnie's side.

"Funny how things change in 10 years," Clampett said.

He had just finished a press conference after a one-under 71 left him in fine position for a victory that would defy belief. To win for the first time in his nearly two years on tour, literally in his backyard, with face after familiar face dotting each fairway, would be . . .

Well, it would be close to a logical progression.

Clampett may be golf's next shooting star. Winner of $184,710 last year, his first full one on tour, and among the top 20 on the money list this season he has experienced nearly everything except victory.

The first tournament Jack Nicklaus and Lee Trevino won as pros was the Open, Clampett was reminded. His eyes brightened, although all he said was: "That's interesting."

He is as cautious in public as he will be in the Open. At Pebble this week, that is prudent and safe, for the right hand he hurt during the first round of the Kemper two weeks ago at Congressional is just now feeling fine. Only today has he dared use that hand to greet friends.

His round today was not quite what he wanted, but more than acceptable. He made birdie twice when that was possible, on the fourth and seventh holes, and saved par three times when bogey was probable. His one above-par hole, the 10th, came after he topped a three-iron from a fairway trap.

"The Open in '72 was a turning point for me," he said. "That really turned me on to golf. David Graham only recently paid me for shagging all those balls; I watched the final round on TV, and screamed when Jack hit the stick with that one-iron at 17.

"I didn't know a good shot from a bad one, and I remember Arnie being furious when one of his practice drives was a few feet off. Somebody yelled: 'One out of 60 ain't bad.' "

Clampett's father died that year and he his mother moved to a home adjoining Carmel Valley Golf and Country Club. Through his own wits and generous pros, he had entrance to some of the toughest, most famous courses in the country.

When he chose to skip assembly at Robert Louis Stevenson High, he could practice trouble shots from off the 17th fairway at Spyglass and still make the next class. That was his school's home course for matches. The better he played the more accommodating the pros and Cyprus and Pebble Beach became.

At 15, during the Insurance Youth Classic, Clampett sensed he could earn a comfortable living at golf. He won the junior part of the tournament; more important, from the same tees, his even-par 144 was just four shots off the winning pro score.

"I tied Rod Funseth and Larry Ziegler," he said. "Tom Watson was five shots higher than me. Of course, I was trying harder. For them, it was sort of a walk through the park. I remember outdriving Eddie Pearce, and later thinking: 'Maybe I can play with these guys.' "

He can.

Although he has played Pebble perhaps 100 times, that is not the overwhelming advantage it might seem. The competition, after all, plays the course each year during the Crosby. But no subtlety escapes him, for he has lost and won donuts, and more, trying to recover from nearly every possible trouble spot, wet and dry.

Mostly, what he saw today was gorgeous: shots splendidly placed, thrilling scenery, scores of friends and neighbors outside the ropes. It was a day to savor years from now by an autumn fireside, as good as golf ever gets for many players. His peers say Clampett is destined for more stunning ones.