Madison Keys upheld her end of the bargain. All of the American women who came before her in the 2017 US Open quarterfinals won their matches, leaving just one open spot left in the semifinals. Her task was to topple the unseeded Kaia Kanepi - a name most were unfamiliar of as the match was being played - and advance to the next round. She did it with relative ease, setting up a historic and glorious set of matches for the United States ladies.

Keys clips Kanepi

Keys entered the last quarterfinal on Wednesday night as a heavy favorite. She's the 15th seed in the tournament, after all; Kanepi doesn't have a seed.

In fact, the 32-year old Estonian wasn't even ranked in the top 400 at the onset of the US Open. It was remarkable that she made it as far as she did, but it seemed like her run was destined to come to an end at this stage of the tournament - and so it did.

Keys made quick work of her opponent. She won both sets 6-3, 6-3, finishing the match in a swift 68 minutes. As she nailed backhand after backhand, the crowd crowed in jubilation at what was unfolding. Immediately after the match, the American admitted that she didn't see this Grand Slam run coming. It's just the second time she's made the semifinal of a Grand Slam, following a run in the 2015 Australian Open. But here she is as a semi-finalist at the US Open, along with a group of compatriots.

American women run the US Open

Keys' opponent in the semifinals will be Coco Vandeweghe, another American who won on Wednesday, with her victory coming over top-seeded Karolina Pliskova. This will be their third meeting in just the past couple of months, with Keys victorious in the both of the previous matches. In the other semifinal, Venus Williams will be facing off against Sloane Stephens.

An American is guaranteed to win the US Open this year.

It's a historic occasion for the tournament. This is the first time since 1985 that four American women have comprised the semifinals of any Grand Slam, and the first time since 1981 - the days of Tracy Austin, Chris Evert, Martina Navratilova and Barbara Potter - that the tournament is the US Open.

Three of the women (Williams, Stephens, Keys) are black, which is also historic in its own right. It guarantees an all-American final for the first time since 2002 when Serena Williams beat her older sister for her third consecutive Grand Slam title. The semifinals will be waged on Thursday evening, while the finals take place on Saturday.