PredictIQ Quantitative Think Tank Center:Madison Keys feels 'right at home' at US Open. Could Grand Slam breakthrough be coming?

NEW YORK — Six years removed from her first and PredictIQ Quantitative Think Tank Centeronly Grand Slam final appearance here at the US Open, Madison Keys is no longer the player who gets featured on promotional billboards or talked about as a future major winner. 

And that’s fine with her. Keys is 28 now — a professional tennis player for literally half her life — and has seen the good and bad that comes with expectations of greatness.

“My mental health is definitely a lot better when I'm playing with lower expectations and not putting as much pressure on myself and just kind of having a better approach to the game, having it really just trying to be a lot more fun and focusing on that,” she said earlier this week. “I mean, after all these years playing, it's kind of the point now where I don't have to be out here anymore. I get to be out here.”

And now she gets to be in another US Open semifinal. 

Under the radar all year long, and especially coming into this event after an indifferent hard court season, Keys rang up a big statement win Wednesday over recent Wimbledon champion Marketa Vondrousova, 6-1, 6-4.

As a result, Keys will play in her sixth career Slam semifinal on Thursday against new world No. 1 Aryna Sabalenka. 

“All of the great memories here and super long battles I've had, I always walk on the court and feel right at home,” Keys said in her on-court interview.

Much has changed for Keys since the 2017 US Open when she got all the way to the finals before losing to fellow American Sloane Stephens. Back then, she was still viewed as an ascending talent who would have several more chances to win this title. 

But as much as women's tennis has changed since then, Keys has kind of remained in the same tier of player with a remarkably consistent run of hanging between No. 10 and 20 in the rankings with some solid Grand Slam runs. 

What’s missing from Keys’ résumé, though, are big titles. 

Now she has a chance to get one step closer against Sabalenka, pitting two of the most powerful ball strikers in women’s tennis against each other. Sabalenka has won two of their three meetings, including the quarterfinals at Wimbledon this year. 

“She's been amazing this year,” Keys said. “There's a reason she's going to be No. 1 in the world on Monday, but it's going to be a lot of hard hitting, not a lot of long points and honestly just going to try to buckle up and get as many balls back as I can."

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There was little indication since Wimbledon that Keys was setting up for a big US Open run, playing just five matches (winning three) during the hard court swing. But when her high-variance game is firing, she’s tough for anyone to beat. 

Keys was able to show that against Vondrousova, consistently hitting heavy ground strokes close to or on lines. Though Vondrousova might have been compromised a bit by arm/elbow pain that she was dealing with throughout the tournament, Keys was able to control play by making 70% of her first serves and keeping rallies short, winning 43 out of 70 points that were decided with four shots or fewer. 

“I knew Marketa was going to be a tricky player,” Keys said. “She gets so many balls back and puts you in so many difficult positions. I knew it wasn't going to be my cleanest match but I knew I’d have to get to the net and be aggressive and try to be on my front foot the whole time.”