The richest bonanza in the history of golf - the $100,000 first prize in the World Series of Golf - produced a spectacular afternoon of head-to-head shot-making today.

Lanny Wadkins - the cussin', wisecrakin', hell-bent birdie glutton - survived a phenomenal 29 over the front nine turned in by playing partner Tom Weiskopf, then came home firing "B's" of his own for a 65 that not only beat the fieldby five strokes but set a Firestone Country Club record of 267.

Wadkins' performance was almost too full of superlatives to be credible. Weiskopf's 29-36-65 onslaught would have destroyed any golfer less confident than the cocky Wadkins. The 5-foot-8 gambler started the day with a five-shot bulge on Weiskopf and thought he would only have to beat conservative Hale Irwin in the group ahead to hold his one-shot third-round lead.

But Weiskopf came out of the chute with an amazing display of golf and gamesmanship. He not only started birdie-birdie-birdle-birdie-par-birdie, par-birdie, but pulled out every hustler's trick of trying to upset Wadkins by disrupting his rythm of play.

By the time they reached the ninth tee, Wadkins' lead was gone. The pair - one the tall, classic ball-striker, the other a stubby scrapper - stood alone on their private Olympus, both nine under par and no one within three shots of them.

Weiskopf admitted later that he had thrown the finest streak of gold of his entire life at Wadkins. "I threw everything at him. It's the best I've ever played. I could conceivably have birdied all of the first 11 holes. I didn't miss birdieing any of them by more than a fraction of an inch."

Far from being intimidated, Wadkins thought the whole affair was a picnic. At the sixth hole, after both had birdied that 465-yard legend, the two exchanged smiles of mutual respect and elation that would have been worthy of Butch Cassidy and Sundance Kid.

"Come on, Kid. Let's shoot the lights out of this joint," Weiskopf's grin seemed to say. "Right with you, big fellow," Wadkins' snapping eyes seemed to respond.

"Hang in there, Lanny," roared the fans. "Stick it in the hole, Tom," answered others.

When the two reached the eighth tee Wadkins broke up Wieskopf and the crowd by saying, "Jeez, this is fun."

Afterward he mused: "Just being in the middle of it was incredible. We were destroying this great course and leaving everybody behind. The crowd was going nuts. I was just havin' a ball."

But when Weiskopf birdied the eighth to wipe out the last of Wadkins' margin, it was time for serious business.

"It's easy to get to watchin' Tom," said Wadkins. "He plays a different game than a lot of us."

Weiskopf thought he had Wadkins on the ropes and at the brutal 465-yard par-four ninth he ripped the biggest drive of the day, a roaring draw that landed like a white bird on the horizon.

Wadkins could have cracked. Instead, he may have hit the biggest drive of his life. The second white bird landed.

"I ripped mine," said Weiskopf as they left the tee.

"Yeah, so did I," said Wadkins.

Weiskopf, who had been leaving Wadkins in the dust off the tee all day, instinctively walked to the ball 35 yeards nearere to the green. His double take when he saw it was not his, may have been the turning point of the day.

"Use your driver next time, Tom," hollered a fan as Weiskopf shame-facedly trugdged to his ball.

Wadkins, so recently in disstress, relished the moment. "Tom couldn't believe it," he said later, laughing. "He said, "I think there's something wrong with this ball. The center must have exploded. I want to declare it unfit for play."

Wadkins laughed with delight. "He was serious. He just didn't think I should be 35 yards past his best drive."

Weiskopf hired to within 15 feet, but Wadkins blanketed the stick with a knock-down nine-iron shot.

Weiskopf's birdie putt for a 28 looked in the front edge of the hole, didn't ll l ike what it saw, and broke away a half-inch left. Wadkins ran his eight-footer down the drain and leaped in the air, pumping his fist.

The World Series had turned with a Sunday bag full of $100 bills shifting hands. Weiskopff's binge had ended. His marvelous ball-striking continued, but at the 10th and 11th his makeable 15-foot putts just trickled past.

Wadkins saw his moment. "I just poured on the coals," he said. A 300-yard poke at 10, a wedge to four feet that almost bit the stick, and a gentle tap-in for birdie, put Wadkins back in charge by two shots with no one else in sight.

Any hope of a Weiskopf comback died at 12, the hole that enneded this championship for all practical purposes almost before the national TV cameras tuned in.

Wadkins, up first, ripped a five-iron shot on the 180-yarder to 10 feet. Weiskopf, after 11 holes of most magnificent golf, finally pushed an iron shot to the right-into the crowd.

Weiskopf faced a clear 25-yard uphill chip. But he managed to find an exposed telephone jack three yards short of the e green that bothered him. Only a poor, weak wedge could have come close to the socket, but Weiskopf got it into his mind, ased for a ruling, had the jack unplugged, then walked about his shot several times.

Weiskopf subsequently fluffed his chip shot and the ball landed directly on the three-by-six-inch jack and stopped dead in deep grass. The plug had been pulled on Weiskopf's charge. He "saved" a bogey, but Wadkins was in the driver's seat. He ran down his putt fffor the birdie, the ball circling the cup and dropping.

The lead that had disappeared was suddenly four shots over Weiskopf and five over Hale Irwin, who eventually rallied to tie Weiskopf for second at 272.

From that point in, Wadkins fired for the record books. Ray Floyd's 268 here in 1969 was considered one of the unreachable scores in golf. After all, only one man (Bobby Nichols, 272) had ever come within six shots of Floyd's incredible mark.

But Wadkins knew his numbers and he wanted 267. At 13 and 14 Wadkins drove wildly, but saved pars thanks to a marvelous "knock-down, cut three-iron about 220 yards" and a high, tree-skirting hook from a fairway bunker.

At the 16th, Wadkins showed the sort of brilliant lunacy in strategy that is marked with a "!!??" in chess notation.

For the lie in the rough, Wadkins cut a wedge less than six feet over a fronting pond, stiffing the pin for a tap-in bridie.

Saner men would have played safe with a big lead, but Wadkins is the reigning free spirit of the tour, the streaky kid who says "I hit every shot at the flag no matter what. If I can see it, I aim at it. Kinda makes the game simple."

Thanks to a short birdie at 17. Wadkins could relax and three-putt the 13th for a meaningless final bogey that robbed him of a gaudy 64. "That was my first three-putt in 72 holes," he said.

Wadkins won with tremendous joie de vivre and good fellowship today. Others, like Floyd just a day ago, have gotten furious with Weiskopf's gamesmanship. For the first five holes Weiskopf got to the see-no-evil Wadkins with an ancient caddie-yard trick - walk double time to your ball to make your short-legged opponent huff and puff, then stall over your shots to make him wait and think about his. Since Wadkins walks very slowly, but plays his shots very quickly, the strategy had Wadkins tied in a knot until he wised up and slowed to a comfortable pace and ignored Weiskopf.

"I would never pull (for) anyone to hit a bad shot," said Wadkins pointedly. "I was pulling for Tom to shoot 61 if I could beat him by one." As it turned out, he would have.

A year ago this Labor Day, Wadkins was deep in an awful slump, far out of the top 60 and wondering if his teen-aged and early 20s greatness would ever return. "I was sittin' home fishing and drinking beer this time last year," he clucked.

Now, in a month, he has won the PGA with its lifetime exemption, and the World Series with its hundred grand. "I don't think the PGA has even sunk in yet," said Wadkins. "When I walked up to the 18th green and they said Here's the PGA champ. I looked around to see who the hell it was."