In a women’s draw that saw the defending champion eliminated in the first round, only two Top 10 seeds reach the quarters and no Top 8 seeds advance to the semis, this final makes perfect sense: unseeded Sloane Stephens versus No. 15 Madison Keys.

In Open era history, only once has there been a final featuring two lower-seeded players: 2015, when No. 26 Flavia Pennetta defeated Roberta Vinci in an all-Italian final.

Two years later, it’s all-American.

Six weeks ago, Sloane Stephens was ranked No. 957 in the world, her ranking having plummeted following foot surgery that necessitated an 11-month layoff. Keys, meantime, dropped out of the Top 20 after two left wrist procedures nearly derailed a season she only got back on track this summer.

On Saturday, these two promising talents – once touted as future stars, then doubted as perhaps too fragile – will play in the first all-American US Open women’s singles final since Serena Williams defeated sister Venus 15 years ago. It is a fitting finish to a topsy-turvy two weeks, with a first-time American champion at America’s Grand Slam.

With that, here’s a look back at Day 11 and a look ahead to Day 12 – men’s semifinal day – at the 2017 US Open:

play video Performance of the Day: Sloane Stephens

Match of the Day

In an encounter that was equal parts captivating and confounding, 37-year-old, nine-time US Open semifinalist Venus Williams and 24-year-old, first-time semifinalist Sloane Stephens put on a display of streaky tennis that alternated – typically for prolonged stretches – between brilliant and downright bizarre. In fact, never in the match, not once, did either player ever win fewer than two consecutive games – an almost impossible statistic in a sport that is predicated on trading (and thus holding) serve.

The two Americans both advanced to the semifinal stage by winning third-set tiebreaks in the round of 8 – stanzas that required as many games (13) as their first two semifinal sets combined.

After Stephens won the opener, 6-1, and Venus countered in the second set, 6-0, the two settled into a third set that finally narrowed the daylight between the two – but that still managed to continue the match’s own cockeyed cadence.

Stephens shook off a second-set shutout to go ahead 2-0 in the decider, then promptly dropped the next three games, then won the next two, then lost the next two.

Then the match turned fantastic. At 30-30, down 5-4 in the final set and two points from defeat, Stephens hit one of the best shots of the tournament, a flat-footed, down-the-line backhand that sizzled past a stunned Venus. Stephens won the game on the next point. And at 5-5, she executed a perfectly placed drop shot on the dead run, going on to break Venus at love to go up 6-5.

From there, Stephens served it out, winning the last three games to produce a score line that was as odd as the match that produced it – a 6-1, 0-6, 7-5 victory that delivered Stephens into the first Grand Slam final of her young career.

play video Keys vs. Vandeweghe

Player of the Day

At the 2017 US Open, the night belongs to Madison Keys. She played until 1:45 a.m. – the second-latest finish for a women’s match in recorded US Open history – to win her third-round match over Russian Elena Vesnina, came back two days later to close out the evening session with a three-set upset of No. 4 Elina Svitolina and, on Wednesday, whipped qualifier Kaia Kanepi in the evening to reach her first US Open semifinal.

On Thursday, she proved that practice does indeed make perfect – or at least it comes awfully close. Playing her fourth consecutive night match, Keys was nearly flawless, turning what was expected to be a taut tilt into a lopsided affair, dismissing friend and countrywoman CoCo Vandeweghe, 6-1, 6-2, to advance to her first Grand Slam final.

The match was a master class in power tennis. Keys produced 25 winners to just nine unforced errors, controlling the encounter with her high-octane serve and supersonic ground game. And with that, the highly touted junior has an opportunity to win the Grand Slam title that so many had long predicted for her – having finally harnessed her powerful game at age 22 and matured into a title threat, and perhaps in two days’ time, a US Open champion.

Upset of the Day

The matchup was one round away: the kings of New York against the top seeds for the 2017 US Open men’s doubles title. But it has been an unpredictable US Open, and on Thursday, even the doubles draw followed suit.

First, the 12th-seeded duo of Jean-Julien Rojer and Horia Tecau upended No. 1 seeds Henri Kontinen and John Peers, 1-6, 7-6, 7-5, and then the all-Spanish, totally unrelated duo of Feliciano Lopez and Marc Lopez ended a run at a sixth men’s doubles title for Bob and Mike Bryan with a 3-6, 6-3, 6-4 victory.

And with that, Friday’s men’s doubles are set – and a first-time men’s doubles champion is assured.

Number of the Day

4: The number of unseeded women in the Open era who have advanced to the US Open women’s singles final, with Sloane Stephens this year joining Venus Williams in 1997, Kim Clijsters in 2009 and Roberta Vinci in 2015. Of the previous three, only Clijsters won the title.

Quote of Day

“For me, it's about putting myself in the position all the time to get the titles, and that's exactly what I did. That's all I could do. So that's the point of being here is to put yourself in position to win.” – Venus Williams, after her three-set semifinal loss to Sloane Stephens, on whether she was frustrated at reaching the semifinals or better in three Grand Slam events this season but not having won a title

play video Venus Williams Interview

Day 12 Preview

The men’s singles semifinals take center stage on Day 12, with Spain's Pablo Carreno Busta facing South African Kevin Anderson and top-seeded Rafael Nadal playing No. 24 Juan Martin del Potro to set up the 2017 US Open finale.

The matchup between No. 12 seed Carreno Busta and No. 28 Anderson marks the first time since 2002 that two double-digit seeds have played in the men’s semifinals (No. 17 Pete Sampras vs. No. 24 Sjeng Schalken). Carreno Busta is the only player in the singles draws, man or woman, to advance to the semis without having surrendered a set, prevailing over four qualifiers and No. 29 Diego Schwartzman to reach the round of 4. Fellow first-time Grand Slam semifinalist Anderson, meantime, has ridden his big serve to this stage and is coming off a stirring four-set, night-session quarterfinal win over Sam Querrey.

The second semifinal features a pair of fan favorites and former champions. No. 1 Nadal has cruised through his last two matches and enters Friday as the far more rested of the two men; del Potro is coming off a two-sets-down comeback to defeat No. 6 Dominic Thiem in the fourth round and a draining four-set victory over five-time champ Roger Federer in the quarters. This is the first Flushing matchup between these two since 2009, when del Potro blitzed Nadal, also in a semifinal, en route to his lone Grand Slam crown, with Delpo looking to return to the title match for the time since that match and Nadal pursuing a fourth trip to the men’s singles final.