Three days ago, Wang never held a lead in the LPGA. Now, she held a trophy.

Thanks to a clutch birdie on the 17th hole, Wang won the second FM Championship at TPC Boston, shooting 20 under par for her first career LPGA Tour victory.

Wang and world No. 1 Jeeno Thitikul battled all afternoon, several strokes ahead of the field in a head-to-head battle akin to a heavyweight title fight.

Wang landed the knockout punch on 17, a 392-yard par-4 that takes a sharp dogleg left and requires an accurate approach into a postage stamp green, guarded by a deep bunker on the left-hand side.

After a great drive, Wang felt comfortable with a 9-iron approach, a shot that she perfected during the second round. Wang pulled the same rabbit out of the hat, enacting a bit of deja vu to put herself in a good position.

“I’m pretty confident with that hole,” said Wang. “That hole just works for me. But honestly, the second shot was not easy. It was not visually comfortable to anyone, I think. It’s a hard pin position.”

A tricky left-to-right 5-footer awaited her, which she drained.

The gutsy birdie perfectly encapsulated Wang’s resolve. The wheels could have fallen off the bus after a pair of shortcomings. She bogeyed the 370-yard, par-4 15th and fell a shot off the lead.

She responded well by throwing a dart near the pin of the 120-yard, par-3 16th, but her birdie attempt veered past the right edge of the cup. Another opportunity missed, yet Wang’s steadfast determination prevailed.

“It’s been a lot of growth,” said her caddie, Jay Davey. “Just through golf you might get rattled, but now she stays so calm. She’s level right now. A bogey or a birdie, she’s the same person.”

Thitikul let the lead escape her grasp on the penultimate hole.

The undulating green guarded the pin against Thitikul’s third shot, a chip that required a robust shot shape. Mired in the thick rough, the grass grabbed her club and her chip ended up off the green. She retried her effort from the other side and tapped in for a bogey.

Jeeno Thitikul’s attempt to tie Miranda Wang at 20-under slid just wide of the 18th hole.Danielle Parhizkaran/Globe Staff

“I think the second shot was so above my feet,” recalled Thitikul. “I don’t want it to go right of the pin because it’s going to be hard to bounce back, right? And then I thought it wasn’t going to take too much left [as it did].”

Both players reached the 507-yard, par-5 18th in regulation and two-putted for par. Neither were aware of how the leaderboard stacked up until the final green.

“I will just say to myself, no single day that I haven’t been proud of myself, whatever ranking I am,” said Thitikul.

The LPGA Tour has not had a repeat winner this season through 23 events — including one team event. The sheer amount of parity speaks volumes to the overall depth of the tour. Any given week, someone different can hoist the hardware.

“Being this competitive, I think it’s good for my career,” said Wang. “Prepares me for many years to come.”

Wang is the seventh rookie to win this season. Without a player establishing themselves with a Scottie Scheffler-level of dominance, the next generation possesses a bright and promising path forward. And one thing is for sure: the future is now.

“I just want to keep up with the best,” said Wang. “Don’t want to be left behind.”

Miranda Wang watches her approach shot into the 18th green, putting her in position to capture her first LPGA Tour title. Danielle Parhizkaran/Globe Staff

In the morning, Ariya Jutanugarn drained the only hole-in-one of the tournament, slotting a gap wedge neatly into the cup on 16.

It’s her fourth hole-in-one on tour; she previously achieved the feat in Thailand, China, and Korea.

“No?,” she asked, wondering if she won a prize for her feat. “Why I’m here? Why [do] you need me?”

After receiving a pair of cars for her aces in the past, it’s hard to blame Jutanugarn for being miffed. Upon hearing that the LPGA would donate $25,000 to St. Jude Children’s Hospital for the hole-in-one, her tone changed immediately.

“I just want to say thank you for doing that,” said Jutanugarn. “It means a lot for me, and of course, for all the girls.”

Wang might not have had an ace, but she did live out her dream. When she first watched the LPGA on TV at 8 years old, she knew what she wanted to pursue for a career. One day, she told herself, she’d stand in the winner’s circle.

“That’s what I wanted to do and I want to be on this tour,” Wang said. “I want to win out there. So I finally did this. Very proud of myself.”

Miranda Wang gets the celebratory shower thanks to two of her best friends on the LPGA Tour, Chinese countrywoman Zhang Weiwei (right) and American and Rose Zhang, after capturing the FM Championship Sunday at TPC Boston. Danielle Parhizkaran/Globe Staff

Asked how “Miranda Wang, champion” sounds, Wang’s ear-to-ear smile filled the room.

“It sounds perfect.”

Cam Kerry can be reached at cam.kerry@globe.com.