When an obscure pro named D. A. Wedbring birdied the second hole at Inverness Club today with a sand wedge from a bunker and used his putter at the 15th hole to escape from under a tree, the 79th U.S. Open had officially begun.

The Open annually mixes the zealous with the zany, sometimes intentionally. The U.S. Golf Association might design diabolical courses for its showcase tournament each year, but it does have at least one pixie.

Frank Hannigan gives the opening two rounds much of their appeal. As assistant director of the USGA, he decides who plays with whom until the cut - and no one combines tradition and whimsy with more flair.

There was a reason Mike Reid, Don Padgett II and Stan Thirsk went off as a three-some today, just as there was logic - or at least Hannigan logic - in putting Steve Melnyk, Craig Stadler and Bob Murphy together.

No, Hannigan insisted, he did not offer the latter as an all-fatty lineup, to see if those rotund swingers could in fact walk side by side down the straw-width fairways without somebody stepping in rough.

"They are all former amateur champions," Hannigan said.

Hannigan smiled. That is primarily what separates him from the typical USGA official, whose face usually is about as emotional as a fairway trap. Golf junkies each year leap for Hannigan's pairing sheet to catch his latest innovations.

At Southern Hills two years ago, Hannigan sent the longest hitters in golf, Jim Dent, Andy Bean and Fuzzy Zoeller, off together. The all-gorilla team, Bean called it. Hannigan's special this year was Reid, Padgett and Thirsk.

They are all one-day major-tournament phenoms, men who for one round played golf the immortals would have envied then drifted quickly back into their familiar, anonymous company.

With a 68, Thirsk was tied for the lead after one round in the 1972 PGA championship at Oakland Hills. He shot 82 the next day. Padgett had the low score, a 66, of the third round of the '77 Open. Two shots back the final day, he shot 80.

When every pro was ready to hang the nearest USGA blue coat from the highest magnolia after the first round of the Open in Atlanta three years ago, amateur Reid drifted in almost at dusk with an astonishing 67. He blew back into obscurity the next day.

Some of Hannigan's threesomes are predictible, the British Open champ (Jack Nicklaus) with the defending Open champ (Andy North) and the U.S. Amateur chamion (John Cook). And the Masters champion (Zoeller) with the PGA champion (John Mahaffey) and the low amateur at the Masters (Bob Clampett).

Frequently, enough players who even Hannigan cannot recognize qualify for the Open and get put together at random. At times Hannigan roots for names during qualifications. Hard.

"We had a Byrne (Kip) this year," Hannigan said. "And we had a Money (Monte). I was desperately hoping somebody named Hole - or even Pocket - also would qualify."

But Wayne Levi, Bob Byman and Larry Nelson did qualify - and they went off together this morning, Hennigan's "unknown first-time winners." They left just before Ed Sneed, Severiano Ballesteros and Bean, who Hannigan made a threesome simply because he wanted to see all three play and that was the most convenient way to do it.

Cynics thought Hannigan put Johnny Miller with Tom Watson this year to emphasize the depths of the '73 Open champion's plunge. (Miller shot 40 on the front nine.) And he matched one of golf's slowest players, Joe Inman, with one of the fastest, Rdo Funseth.

"I did have one pairing even the guys at the first tee didn't catch," Hannigan said. "(Jack) Renner, (Eddie) Pearce and (Jim) Masserio. All former (USGA) Junior champions."

Still, there was one significant threesome Hannigan failed to arrange, although he appreciated it. Or at least saw the irony of it, a security-obsessed tournament getting a small pie in the face from Barry Bremen.

Bremen is the fellow with the apparently unique ability to become part of major events. He managed to be a brief part of the NBA All-Star game this year. Wednesday he walked onto Inverness and played nine holes with Levi and Byrne.

"I'm Barry Bremen, an amateur, and this is my first Open," he said to Levi and Byrne on the 10th tee during the final day of pratice. "Could I play the back nine with you guys? I wanted to play the back nine again."

Bremen could.

"He looked to me like maybe he was an amateur just having a bad day," Levi said, adding that Bremen did hit fine tee shots at 10 and 11 before offering several duffer-like hooks and slices. "I really didn't pay that much attention to him. He had a caddie and all - and nobody knows so many of these guys anyway that it's really not all that hard to do what he did."

What Bremen did was shoot about the duffer's dream-even 5s from the blue tees - then introduce himself, as Bremen the professional imposter, as the threesome walked off 18.

"He played the role well," Levi said. "Even chipped and putted with us, took the extra shots around and on the greens we often do after holing out. I didn't mind.

"And something like this happened to me before. This spring, the day before Doral started. Some guy came up to me on the first tee, I even was playing with Kip that day, too, and said he'd gotten a sponsor's exemption into the tournment and wanted to join us.

"We said fine. We got curious right away, though, because he gripped all his clubs crosshanded. And hit every shot bad, much worse than the guy yesterday, 100 yards left and then 100 yards right.

"Finally, the tournament people got wise and dragged him off after five holes." CAPTION: Picture 1, Keith Fergus tees off at 17th; Picture 2, Jack Nicklaus leans head on putter after missing bird on 16 - he finished at 74; Picture 3, Lon Hinkle fails on birdie at 17.