SAN FRANCISCO — Thirteen long, long months since the rowdy roars and roaring rains of Portrush in Northern Ireland at the 2019 Open Championship, major men's golf resurfaced Thursday. It did so in mostly the kind of benign, sweet air that helps make California so populous. Thus it did so with a gush of birdies, in the hush of nowadays.

The first major since the novel coronavirus pandemic ransacked the golf calendar saw the men who have mastered a heartless sport go ahead and maul a 95-year-old course making its major debut, even without spectators to applaud them. Great droves of players hurried under par at TPC Harding Park in the 102nd PGA Championship, a departure from expectations as the not-so-distant Pacific Ocean sat out there and withheld its oomph. As the day often seemed surely among the prettiest in the world, 47 of the 156 players broke par, and 20 more hit it, the trend waning a bit only when the wind got rather huffy near sundown.

"In practice [earlier this week], it was like anything under par would have been a great score," said Shane Lowry, the Irishman from County Offaly who won that last major at Portrush. "But today it was quite gettable this morning, and you can see that from the leader board."

That leader board teemed with so many names bubbling just beneath leaders Jason Day and Brendon Todd and their 5-under-par 65s, notched early in the day (Day) and late (Todd). The chasers included all four reigning major champions: Brooks Koepka (4 under), Gary Woodland (3 under), Tiger Woods (2 under) and Lowry (2 under). Woods, with a vivid history on a course unfamiliar to most, had his best opening round in a major since 2012. So many were the souls bunched just one shot behind Day and Todd — nine of them — that they included both a Scheffler (Scottie) and a Schauffele (Xander) and even the welcome sight of the long-lost Martin Kaymer.

Their group almost included that linebacker of golf, Bryson DeChambeau, who joined seven others at 3-under 67, and whose mighty swings finally subdued his tuckered driver of one year-plus. It broke on No. 6, the head toppling off the shaft after he hit a funky-sounding shot and then leaned on the weary club. "Material isn't going to last forever," he said after replacing the club's shaft.

It's all a lot to untangle, but untangle it they will.

Stare into the stew of names and the most glowing would be "Koepka," whose 66 reiterated there's just something about himself and majors, something reflected in a stat both enviable and quirky: four wins in majors, three in non-majors. Carrying around the rare words "two-time defending champion," he showed that even in a winless bummer of a season with a sort-of-bum left knee, he could sustain the possibility of becoming the first man since Peter Thomson at the Open Championship in 1956 to win any major thrice consecutively. He made six birdies with two bogeys for his 66 and said of major golf, "The majors almost seem like an easier week for me."

"He's got a different driver in the bag this week, and you'd know that," said Lowry, who has joined Koepka for rounds in Florida this strange year. "He drove it long and straight, and he has that little fade back. He'll be hard to beat this week, I'd say."

His last 10 majors: four wins, two seconds, a fourth, a sixth, a 13th and a 39th. He's a man who sees all and reacts to none, as his 10th hole, No. 1, revealed. His face budged hardly half a flinch when he drove it into a pain-in-the-patoot lie in the right rough, requiring a provisional. Then he plunked into a bunker guarding the green.

Then, of course, he made a steely 12-foot bogey save.

"You just try to break it down pretty simply, and I did a good job of that today," said Koepka, who has noted again here this week his philosophy that humans tend to make golf too complicated.

He'll contend for a rare sliver of golf history barring something wacko, but he also could have crowded company to elbow aside if the Pacific keeps refraining from testiness. As said Woods, "I thought anything today in the red was going to be good," soon adding, "I think the winds are supposed to be 17 to 20 [mph]; that was the forecast this morning."

That was only the forecast, and so agony came infrequently on a course where a chopper overhead sometimes supplied the only sound, and where the story lines piled up hastily. Day, the former No. 1 player and the 2015 winner at Whistling Straits in Wisconsin, comes to this after 12 majors in which he ebbed without disintegrating (two top-10s, eight top-30s). The Ohio-based Australian also arrives after three straight top-10 finishes on tour in Columbus, Columbus again and then Memphis, enough to feel "like the game is slowly coming around, the confidence is coming around, because I'm starting to see the results."

Kaymer arrives from greater depths, having spent his past 21 majors drifting toward forgotten, even as a great player still 35 with two major titles including that manhandling of the 2014 U.S. Open by eight shots at Pinehurst. He spent a lot of the pandemic lockdown back home in Germany "trying to help my Dad at the house. We built a terrace, stuff like that." In the inexplicable vagaries of golf, he arrived to the Monterey Cypress trees and to a balm of a course and said, "Expectations were very low, to be honest, because I didn't know where my game was at."

At the par-5 No. 4, it was at 297 yards to the green, and then it was at 47 feet for an eagle, which did occur.

It helped epitomize how the 66s alone seemed to come from everywhere.

Scheffler, a 24-year-old Texas Longhorn, shot his 66 at his first PGA and his fourth major, and marveled. "Yeah," he said, "we expected it to be really cold when we started (at 7:05 a.m., in his case). The sun had barely come up. It was pretty cold but luckily there was no wind. You don't really know what to expect of the weather here because the first day I was coming over from my hotel and it was sunny and I got a text from my trainer, he's like, 'Hey, you still coming out? I can't see 10 feet in front of me [because of fog].'"

"Yeah," Scheffler also said, "the greens are awesome out there."

And: "I think it's a really cool place."

Schauffele, the 26-year-old from San Diego, kept a habit of prowess in majors, his 66 making sense given he has crammed six top-six finishes into his first 11 majors. He had never played here, but said, "I've played across the pond here at Olympic in the Cal State Am, came up with no sweaters or beanies or anything so had to make a lot of purchases in the pro shop," so there's that.

And the 35-year-old French golfer, Mike Lorenzo-Vera, reached 4-under-par, too, then spoke of a familiarity with the conditions that spoke to the era at hand: "I've been here for long now," he said, "because I was quarantining here."

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