NEW YORK — Bianca Andreescu knew this would happen, because she knows all about Serena Williams. Looked up to her. Dreamed of playing her.

Andreescu knew Williams would not go quietly. Knew Williams would not make things easy. And so as a big lead in the U.S. Open final dwindled Saturday, as she stuffed fingers in her ears to drown out the decibels from the delirious thousands filling Arthur Ashe Stadium, Andreescu knew she needed to be just as bold, and hit just as big, as she did earlier in the match — and as Williams has done for years.

Displaying the same brand of in-your-face tennis Williams seemed to invent, replete with strong serves, gutsy groundstrokes and “Come on!” cries, the 19-year-old Andreescu regained the upper hand and pulled out a 6-3, 7-5 victory at Flushing Meadows to win her first Grand Slam title and keep Williams from collecting a record-tying 24th.

“I’m sure I’m not the only person that’s looked up to her. She’s an inspiration to many, many people, not only athletes. What she’s done off the court, too. She’s truly a champion. Above all, she’s very kind-hearted. She came up to me in the locker room, she said some really nice things, which I’ll cherish for a really, really long time,” Andreescu said about the 37-year-old Williams.

“I’ve really strived to be like her,” Andreescu said. “Who knows? Maybe I can be even better.”

That’s quite a heady goal.

Still, this was certainly a good place to start.

Andreescu is the first woman in the Open era, which began in 1968, to win the championship in New York in her tournament debut; a year ago, she couldn’t even make it into the field, because she lost in the first round of qualifying. She is the first woman since Monica Seles in 1990 to lift the trophy in only her fourth Grand Slam tournament. She is the first player from Canada to win a Grand Slam singles title.

This is the second year in a row that Williams has lost in the final at Flushing Meadows. This one had none of the controversy of 2018, when she got into an extended argument with the chair umpire while being beaten by Naomi Osaka.

Williams has now been the runner-up at four of the seven majors she has entered since returning to the tour after having a baby two years ago. The American remains stuck on 23 Grand Slam singles titles, one shy of Margaret Court’s mark for the most in history.

“I’m not necessarily chasing a record. I’m just trying to win Grand Slams. It’s definitely frustrating, you know,” Williams said.

She gave credit to Andreescu for playing well, but also said: “I honestly didn’t play my best today. I could have played better. That’s the only solace that I can take right now.”

Williams double-faulted eight times in all, including three times on break point, part of her 33 unforced errors, nearly double Andreescu’s total of 17.

There were other ways in which Williams was not at her best, seemingly unsure of herself, including one odd-looking check-swing on a backhand in the second set that then let Andreescu put a shot away to go up 4-1.

Soon, Andreescu held a match point while serving at 5-1, 40-30. Williams erased that by snapping a forehand return winner off a 105 mph serve.

That launched a four-game run for Williams, who broke Andreescu again to make it 5-all.

“It was expected. She’s a champion. That’s what champions do. She’s done that many, many times throughout her career,” said Andreescu, perhaps aware that Williams has a winning record even when dropping the opening set of Grand Slam matches. “But I just tried to stay as composed as I could. It’s hard to just block everything out, but I think I did a pretty good job at that.”

Sure did. She steeled herself against Williams, against any nerves, against a loud bunch of spectators and took the last two games.

“Things just start slipping away. You can feel that Serena is finding a little bit of rhythm. She’s finding herself. She’s getting more solid. The crowd is roaring, just getting into it. It’s very easy to say from the sideline, ‘Stay focused, blah, blah, blah.’ But this is overwhelming. There’s no other word,” said Andreescu’s coach, Sylvain Bruneau. “So for her to be able to just, like, reset at 5-all when it’s now anybody’s match, that’s pretty special, I think. Very, very special. It shows a lot.”

She is 34-4 in 2019, 8-0 against top-10 opponents, and without a loss in a completed match since March 1. Andreescu missed a chunk of time in that span with a shoulder injury, which clearly is no longer hindering her.

Andreescu took it to Williams, figuratively and literally. Andreescu produced the kind of power Williams is more accustomed to dishing out than dealing with from the other side of the net. One shot went right at Williams, who leaped to avoid the ball at the baseline.

And Andreescu was fearless, always pushing, always aggressive.

“We’re really similar,” Williams said, “in terms of we both are fighters and we both are really intense.”

Talk about a compliment.

Andreescu agreed. To a point.

“We like to keep the points short with our aggressive game style. We like to use our serve to our advantage,” Andreescu said. “I think we fight really, really hard.”

“But at the same time,” she said, “I want to make a name for myself.”