WHAT HAPPENED: For the second straight day, two young American women competed for a US Open singles title. On Sunday, it was the girls' trophy up for grabs, as Amanda Anisimova and Cori 'Coco' Gauff took to the Grandstand in what was the third consecutive all-American Grand Slam girls' final in 2017.

Anisimova, the No. 4 seed, made her experience count, as she powered her way to a 6-0, 6-2 victory for her first junior Slam triumph. Having just turned 16 during the first week of the US Open, she was the elder statesman against the 13-year-old Gauff.

The second set was much closer than the scoreline suggested, with Anisimova requiring 10 match points in the final game to secure the decisive break, her sixth of the match. Gauff was fearless with her back to the wall in the 28-point service game, earning four game points of her own before a wayward forehand finally gave her opponent the victory.

"That last game was crazy," said Anisimova. "Possibly the longest game of my life."

Anisimova dominated the first set, dictating play with an onslaught of power off both baseline wings. She hit nine of her 20 total winners in the 21-minute opening set, before Gauff raised her game in the second, making it clear she was in it for the long haul.

While the 13-year-old admitted she did not play her best tennis, she was quick to credit her opponent's game. "I thought she did well changing the direction of the ball and hitting winners. I was hitting hard, but she would hit it right back. Most of the time it was down the line, and she was hitting good shots on both sides of the court."

Gauff held serve to get on the board at 1-1 in the secondand created break points in each of her first two return games. She also held a 40-0 lead at 1-2, but Anisimova stormed back to score the break in a 12-point game.

With the momentum firmly on her side, Anisimova continued to extend her lead before winning the trophy in the marathon final game.

WHAT IT MEANS: Anisimova announced that this US Open would be her last time competing in a junior event, and she made it count by winning her first junior Slam trophy. No stranger to the pro tour, she has already earned over $89,000 in career prize money, thanks in part to four ITF final runs in 2017, inlcuding a title in her most recent event in Sacramento. 

Anisimova also appeared in the main draw of the 2017 French Open, after she earned a wild card via a USTA tournament win. She fell short of the US Open main draw in 2016 and 2017, though she did score a win in last year's qualifying tournament, just days before her 15th birthday.

Next up for Anisimova is the junior Fed Cup final in Budapest, Hungary, where she will team with Whitney Osuigwe and Caty McNally in a bid to continue the American domination of the girls' and women's games.

Gauff, who just started eighth grade in her Florida-based online school, was vying to become the youngest girl to win the US Open title and the third-youngest junior Slam champion behind Martina Hingis (12) and Jennifer Capriati (13), who both won the French crown. She plans to play the junior Orange Bowl in December and is still working out her plans beyond that, though her sights are set on more success at the US Open. "I'll definitely be back here," she smiled.

MATCH POINT: We already know Anisimova is headed to the pro tour full time. How long before the precocious Gauff joins her?