WHAT HAPPENED: Madison Keys put on a commanding performance to advance to the first Grand Slam final of her career, defeating fellow American CoCo Vandeweghe, 6-1, 6-2, Thursday night in Arthur Ashe Stadium.

Keys will next face another American, unseeded Sloane Stephens, on Saturday afternoon for the 2017 US Open women's singles title.

Keys and Vandeweghe were meeting for the third time as professionals, all three meetings having come inside this summer swing; Keys was victorious in the final at the Bank of the West Classic in Stanford in straight sets, and prevailed in three at the Western & Southern Open in Cincinnati in August.

 "These are the moments growing up that you dream about, and, you know, to be sitting here as a US Open finalist, it feels really amazing," Keys said. "I played really, really well. It was kind of one of those days where I came out and I was kind of in a zone, and I just kind of forced myself to stay there. I knew I was going to have to play really well in order to beat her, and, you know, I feel like once things started going, it just kind of fell into place."

play video Keys vs. Vandeweghe

The No. 15 seed looked comfortable from first ball under the lights, playing her fifth night match of the tournament overall. A near-flawless first set saw her strike 14 winners to just two unforced errors, as Keys broke twice and dropped just three points overall on serve. 

The second set proved similarly dominant for Keys, with a brief blip: she built a double-break lead at 4-1 before taking an off-court medical timeout due to an apparent leg injury.

However, the wrapping hardly slowed her down for the duration of the match, and she sealed a spot in her first Grand Slam final in style with her fourth ace of the match.

Overall, Keys amassed 25 winners to just nine unforced errors, as she won over 70 percent of the points played behind her first and second serve. Keys never faced a break point in the match, and converted on four of the seven opportunities she created to advance to her first major final in a tidy 66 minutes.

WHAT IT MEANS: Saturday's women's championship will be the first Grand Slam title for either player, as it will be the first all-American final at the US Open since 2002, when Serena Williams defeated her older sister, Venus.

Stephens or Keys will be the first American woman not named Williams to win a Grand Slam title since 2002 as well (Jennifer Capriati), while both are the first American women outside the Williams family to make a Grand Slam final since Lindsay Davenport in 2005. 

"Playing Sloane, I know she's going to get a lot of balls back, and she's going to reset the point over and over again," Keys said. "I'm just going to have to be patient and, you know, not go for too much too soon and just try to keep building points until I finally have the right ball. I definitely never envisioned it happening this way, but I couldn't think of a better person to have this first experience with."

Whether it is Stephens or Keys who will be crowned US Open champion, the next generation of the WTA has thrived in the majors this season: three of the four Grand Slam champions in 2017 will be age 24 or younger.

MATCH POINT: Madison vs. Sloane. Sloane vs. Madison. Who've you got, and in how many sets?