There she was at the top of the heap, ahead of the cream of the crop, in her sport’s grandest stage.

But Yuka Saso turned from virtual hot to relatively cold, losing steam in a backside windup and finished with a 2-under 69 and falling by 2 behind American Amy Olson in the first 18 holes of the rich US Women’s Open in Houston Thursday (US time).

Away from the spotlight of an opener focused on the world’s best and the LPGA Tour’s driving leaders, Saso quietly worked her way with a scintillating start to spike a maiden US major stint, hitting 4 birdies at the front of the 6,617-yard, par-71 Cypress Creek layout.

In a fleeting moment, Saso stood above a slew of top guns and a host of rising stars making up the stellar 156-player field, half of which played the Jackrabbit course, but she stumbled with a wet bogey on the 11th and bogeyed the 18th on a 3-putt miscue.

She was so baffled by her last blunder, shaking her head in disbelief after flubbing a makeable par putt bid from just about 4 feet.

But she insisted her late foldup didn’t have anything to do with her succumbing to early pressure, maintaining: “My goal is just to play (golf), so I didn’t pay much attention to it.”

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The LPGA of Japan Tour campaigner, however, admitted playing a major in the US was different.

"The courses are tough and long. The greens are firm. I have to use the driver off the tee as I have to use shorter club in JLPGA. So, yeah, I think that’s the big difference,” said Saso, who turned down a scholarship offer at University of Georgia after falling short of her LPGA Q-School bid and qualifying for the JLPGA last fall.

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Bianca Pagdanganan, meanwhile, likewise sizzled early with back-to-back birdies from No. 10 of the 6,533-yard Jackrabbit layout, also a par-71, but failed to sustain her charge, hobbling with 2 bogeys and a double bogey against one more birdie for a 72.

But the 23-year-old LPGA Tour driving leader, whose campaign with Saso is backed by ICTSI, stayed well within reach of another weekend stint for the ninth straight tournament as she tied for 37th after prevailing in the featured group of bombers.

Mexican Maria Fassi, who on the eve of the tournament had bragged about flaunting her driving prowess against Pagdanganan and Dutch Anne Van Dam and show “who the boss is,” bombed out with an 83.

Fassi outhit Pagdanganan (265 yards) and Van Dam (269 yards) with a 287-yard average but paid dearly for her wild drives. She missed seven fairways and struggled with her irons, reaching regulation just nine times and finishing with 32 putts.

She shot three birdies but made three bogeys, three double bogeys and a couple of triple bogeys to lay second-to-last and virtually out of the weekend play of the $5.5 million event offering a hefty $1 million purse to the winner.

Van Dam had two bogeys in a birdie-less 73 for a share of 55th with the projected cutoff score pegged at two-over.

Despite her shaky windup, Saso, who normed 267 yards off the tee, actually missed 5 fairways and 4 greens but finished with 29 putts and left an impact on the grand stage, this being her first LPGA Tour appearance and a major championship at that.

She credited her power and putter for her early surge, draining a 22-footer for birdie on No. 2, dominating the 2 par-5s and sinking another birdie from the fringe on the seventh.

“My putting clicked and I feel like I’m doing what I want and I happened to get good results. But it’s just the first round. I hope to do it again,” Saso said.

A different kind of challenge, however, awaits the 2018 Asian Games double-gold medalist in the second round when the field switches courses with Saso, who earned a spot here with an impressive rookie campaign in the LPGA of Japan Tour where she racked up two victories and emerged on top of the prized money race, hoping to make the necessary adjustments on the tighter Jackrabbit with smaller greens.

“Jackrabbit isn’t too short. Like Cypress, I want to keep my shots on the fairways and try to hit the greens and make the most of my chances,” said Saso, now on track to best 2008 champion Inbee Park’s record as the youngest winner of the fabled event.

Starting at the backside of Cypress, Olson bogeyed the 11th but aced No. 16 off a solid shot from the left side of the tee, the ball bouncing off the fringe once before dropping into the cup.

She birdied the next and played so inspired and hit two more birdies at the front for a 67 and a one-stroke lead over three others.

A Lim Kim took the cudgels for a Korean squad that occupies five of the Top 10 places in the world ranking, including No. 1 Jin Young Ko and No. 2 Sei Young Kim, as she carded a 68 for joint second with Thai Moriya Jutanugarn and Japanese Hinako Shibuno.

Kim, winner of the last LPGA Major, the KPMG Women’s PGA, gunned down five birdies but stumbled with three bogeys and limped with a quadruple bogey on the par-3 11th for a 72 while Ko sputtered with a 73 on one birdie against three bogeys.