Venus or Sloane? Coco or Keys? All-American US Open semifinal previews

Their past consists of just one meeting, in the first round of the 2015 French Open, which Stephens won in straight sets. That feels like a lifetime ago considering what’s happened to each American since. Stephens missed nearly a year of competition after last summer’s Olympic Games due to foot surgery, while Williams turned 35, 36 and 37—ages at which players typically retire, rather than continue to excel.

Which brings us to the present. Stephens, after taking two losses to begin her comeback, has improbably gone on one of the best runs of her career: semifinals in Toronto, semifinals in Cincinnati and, now, semifinals at Flushing Meadows. No one could have seen this coming, including Stephens, who was on the brink of tears as she played match point against Anastasija Sevastova.

Williams is vying for her third Grand Slam final of 2017. Serena Williams, who beat her sister to win the Australian Open, didn’t play the US Open; Garbine Muguruza, who beat Venus to win Wimbledon, is out of the tournament. If anyone deserves a major title among the semifinalists—men or women—it’s the always-classy, always-competing 20-year veteran.

Put it all together and you get a very uncertain future. Stephens might be playing the best tennis of her career—and with house money to boot. Her forehand is a potent thing of beauty, a stroke we’ve missed seeing over the past 12 months, and she’s competing with renewed focus and purpose. Williams at her peak probably beats Stephens at her peak, but she also probably faces the most pressure among the U.S. quartet. Still, her comeback victory of Petra Kvitova and those two decades of experience shows she can handle the moment.

There might not be a tougher match to call for the rest of the tournament.

Winner: Venus Williams

Unlike Williams vs. Stephens, this all-American semifinal gives us more history to glean from. It’s recent history, too: in early August, Keys took down Vandeweghe in the Stanford final, 7-6 (6), 6-4; two weeks later, in Cincinnati, Keys once again got the better of her compatriot, this time by the closer margin of 6-4, 3-6, 6-3.

In team sports, as they say, you can throw out regular-season results once the playoffs come around. But while the US Open is unquestionably more significant than Stanford and Cincy, that doesn’t mean we should discount Keys’ unquestioned—for the moment—edge. In a clash of similarities, principally some of the tour’s biggest serves and forehands, there isn’t much that separates these two heavyweights. This match will come down to physical execution, of course, but the mental approach each woman brings to bear will dictate the result to an equal if not greater degree.

“The fact that we're playing three times in a row is interesting,” Keys said after her one-sided quarterfinal win over Kaia Kanepi. “I think I'm just going to have to stay at my highest level and just wait for my opportunities when they come.”

The good news for Vandeweghe is that, from a mental standpoint, she’s in the best shape of her career. (Physically, perhaps, as well.) Some of that can surely be attributed to her new coach, former Wimbledon champion Pat Cash.

“Channeling my intensity and tenacity out onto the court and putting it into a singular focus—I think that's probably one of the biggest things he's implemented into my regimen,” said Vandeweghe after her upset of top-seeded Karolina Pliskova.

Keys probably believes she has the edge in this match, and rightfully so. But Team Vandeweghe is likely positioning Thursday night’s encounter as the final act of a slow-burning trilogy, the act where the plot turns decidedly. If nothing else, Vandeweghe remains confident in spite of her 0-2 mark against Keys.

“I think it depends on me, mostly,” said Vandeweghe, “because similar to today [against Pliskova] and the other day against Lucie [Safarova], Madison is a player that can take control of the points and of the rallies. I think if I allow her to do that, then she's going to be on the winning side of the coin.”

In team sports, they also say, it’s hard to beat one team three times in a season. To reach her first Grand Slam final, Keys will have to beat Vandeweghe three times in one month. That’s really hard.

Winner: Coco Vandeweghe