NEW YORK (AP) — This was what so many folks figured Coco Gauff would do at some point. Didn’t matter how young she was. Didn’t matter whether there were setbacks along the way. Those outsized expectations did not make the task of becoming a Grand Slam champion as a teenager any easier — especially when that chorus was accompanied by voices of others who doubted her.

She did it, though. At age 19. At the U.S. Open, where she used to come as a kid with her parents to watch her idols, Serena and Venus Williams, compete. Gauff set aside a so-so start and surged to her first major championship by coming back to defeat Aryna Sabalenka 2-6, 6-3, 6-2 in the U.S. Open final on Saturday to the delight of a raucous crowd that was loud from start to finish.

When it was over, when she had shed tears of joy, when she had hugged Mom and Dad as they cried, too, Gauff first thanked them, and her grandparents, and her brothers, one of whom failed to answer a FaceTime call from her right after the match. And then Gauff took the microphone during the ceremony to address anyone who might have questioned if this day would arrive.

“Thank you to the people who didn’t believe in me. Like a month ago, I won a (tour) title and people said I would stop at that. Two weeks ago I won a (tour) title and people were saying that was the biggest it was going to get. So three weeks later, I’m here with this trophy right now,” said Gauff, who is on a career-best 12-match winning streak. “Tried my best to carry this with grace, and I’ve been doing my best, so honestly, to those who thought they were putting water in my fire: You were really adding gas to it and now it’s really burning so bright right now.”

Gauff, who is from Florida, is the first American teenager to win the country’s major tennis tournament since Serena Williams in 1999. If last year’s U.S. Open was all about saying goodbye to Williams as she competed for the final time, this year’s two weeks in New York turned into a “Welcome to the big time!” moment for Gauff.

She burst onto the scene at 15 by becoming the youngest qualifier in Wimbledon history and making it to the fourth round in her Grand Slam debut in 2019. She reached her initial major final at last year’s French Open, finishing as the runner-up.

What appeared to be a step back came this July at the All England Club, where she exited in the first round. Since then, she’s won 18 of 19 contests while working with a new coaching pair of Brad Gilbert and Pere Riba.

The No. 6-seeded Gauff did it Saturday by withstanding the power displayed by Sabalenka on nearly every swing of her racket, eventually getting accustomed to it and managing to get back shot after shot. Gauff broke to begin the third set on one such point, tracking down every ball hit her way until eventually smacking a putaway volley that she punctuated with a fist pump and a scream of “Come on!”

Soon it was 4-0 in that set for Gauff. At 4-1, Sabalenka took a medical timeout while her left leg was massaged. Gauff stayed sharp during the break — it lasted a handful of minutes, not the 50 during a climate protest in the semifinals — by practicing some serves.

When they resumed, Sabalenka broke to get within 4-2. But Gauff broke right back, and soon was serving out the victory, then dropping onto her back on the court. She soon climbed into the stands to find her parents.

“You did it!” Gauff’s mom told her, both in tears.

Sabalenka came into the day with a 23-2 record at major tournaments in 2023, including her first Grand Slam title at the Australian Open in January. The 25-year-old from Belarus already was assured of rising from No. 2 to No. 1 in the WTA rankings for the first time next week.

But she was reduced to the role of foil by the fans. As often happens when an American plays in America, Gauff was the recipient of by far the most support from the seats in 23,000-capacity Arthur Ashe Stadium. Her pre-match TV interview, shown on the video screens in the arena, was drowned out by the sound of applause and cheers reverberating off the closed retractable roof.

Even in the early stages, winners by Gauff were celebrated as if the match were over. So were Sabalenka’s miscues. Her faults and, especially, double-faults — and there were six in all, three in her first two service games alone, plus another to hand over a break in the second set — and assorted other mistakes, including one over-the-shoulder backhand volley into the net and what appeared to be a much simpler forehand volley.

By the end, Sabalenka had made 46 unforced errors, far more than double Gauff’s total of 19. Here’s another way to view it: Gauff only needed to deliver 13 winners to accumulate 83 points Saturday.

When Sabalenka has everything calibrated just right, it’s difficult for any foe to handle it — even someone as speedy, smart and instinctive as Gauff, whose get-to-every-ball court coverage managed to keep her in points few other players would be able to extend.

Somehow, Gauff began doing that again and again. And Sabalenka began to miss again and again, frequently slapping her thigh, muttering or shaking her head afterward.

They traded early breaks to 2-all, before Sabalenka grabbed the next four games to take that set. During that stretch, there was a thrilling point that had the audience making noise before it was over. Gauff scrambled to keep getting Sabalenka’s strokes back over the net, including somehow deflecting a booming overhead on the run, before a second, unreachable overhead bounced off the ground and into the stands.

Sabalenka raised her left hand and wagged her fingers, telling the folks in the stands to give her some love. But soon, Gauff was playing better, Sabalenka was off-target more, and the love was being showered only on one of them, the sport’s newest Grand Slam champion.