How Madison Keys is Fueling Her Finish to the 2025 WTA Season

American women's tennis star Madison Keys is nearing the end of her best year on tour. Keys won her first Grand Slam title, enjoyed her longest win streak, and reached a career high in the WTA Rankings.

In a sport that benefits young players with fresh legs, Keys is still improving at 30 years old. After spending more than half of her life on tour, Keys' relentless work ethic and commitment to a healthy routine are helping her unlock new levels.

Keys is a Thorne ambassador, a brand certified by NSF, and considered the "gold standard" for quality in dietary supplements. Sports Illustrated's Serve On SI spoke with Keys about her supplement routine, career year, and goals for the end of the 2025 WTA season.

As a longtime fan of Thorne, how has the company been to work with over the past few years?

Thorne has been absolutely amazing to work with. I think the number one thing as a professional athlete, when you're looking for supplements, is you want to be able to trust what you're taking. It's always probably one of the biggest fears that we have is just making sure that we 100% trust what's actually in the supplement and where it's coming from.

So just being able to completely and utterly trust Thorne and never have any concerns, I think is hand down just one of the biggest parts of working with them.

Have you had to make any adjustments to your supplement regimen during the season, or has it been consistent?

I keep it pretty consistent. I kind of just take the same things all throughout the year. The only thing that I have done in the past is that I've occasionally taken one of the Thorne gut tests and either added or subtracted supplements, based on those results, which was very helpful. But once it becomes routine, I like to just kind of keep that routine throughout the year.

It's late in the season. How are you feeling physically as you push toward the WTA Finals?

Good. It's definitely the later part of the year. Unfortunately, I lost early at the U.S. Open, but I think I'm trying to kind of take that as, you know, as many positives out of that as I can and use that for time to get 100% healthy, more time on the court to kind of just get ready for the last push and really just trying to end on the brightest note that we can.

How did you deal with the US Open loss? Were there takeaways, or was it just a "burn the tape" kind of match?

I think there's a little bit of both. I definitely look back at it and see a few things that were things that I kind of wish that I had a little bit more time to work on or focus on, but have now been able to have that time to really focus on it.

But then at the same time, it's like, I'm not going to sit here and dwell on it days and days later and beat myself up about it, because, realistically, everyone has those bad days. So it's just more taking what you can learn from it and then just moving on and finding the positives in it.

With this year's Grand Slams over, what tournaments do you have your eyes on?

Kind of all of them. They're all big, they're all important. Going into Beijing and Wuhan, both Master's, so I think I would really love to have a really good last push. And then, obviously, making my second year-end finals is a huge goal of mine, so really just kind of positioning myself to be in a good place for that.

How would you grade your 2025 season?

I mean, in a lot of ways... I don't think I've ever won this many matches in a year before. I've obviously been ranked at a career high, I won my first Grand Slam, so lots of positives. But I think the beauty of having a great year and being the veteran that I am at this point in the sport, I think there's still lots of room for improvement.

And I think there's a lot of things that I can actually improve upon and become even better. So I think, I don't know, maybe I'll give myself, like, a B+ with some room for improvement, and hopefully, I can improve upon some of the things next year.

You recently teamed up with Jessica, Jenny, and Desirae for The Player's Box podcast. How much fun has that been to work on?

It's been really fun. We have joked about having a podcast for many years. Then Nothing Major came out, and we were kind of kicking ourselves a little bit because we were like, 'Dang it, like, we had that idea. We should have just gone for it.'

Then I will actually say, it's like the guys from Nothing Major, like John, Sam, and Stevie, have been so helpful, and they were the ones that told us, like, you guys should absolutely just do it. Like, just go for it, try it out. It's been really fun.

We've been having a really great time. And it's been really nice to just kind of see all the feedback that we've got from it. Fans are really enjoying some of what we see as typical days and normal things. A lot of fans don't get to see that. So it's been really fun to kind of pull back the curtain a little bit on our day-to-day lives.

Besides winning the Australian Open, what has been your second-favorite moment of the year?

I think it's really just been the way that I have continued to try to get better. It's obviously been a career highlight to win your first Slam and then go into Indian Wells and have the longest winning streak that I've ever had. So that was really fun. And just taking on new challenges as they come after this many years on tour.

Sometimes you are a little bit surprised that new challenges come up, but just taking them head-on has been something that I'm proud of. So I don't know if I could say, like, one specific moment or so, just kind of the cumulative year.

Who is your favorite player to watch?

I have a lot. Tennis is pretty exciting right now. Obviously, I love watching Jess play just as a friend. I like watching Des play, obviously. I really enjoy watching Ben Shelton play. I could just honestly just list all of the Americans. I really love watching them.

It's super fun to see all of your friends doing really well. And then watching Aryna has been pretty incredible this year. And then, I mean, Carlos and Jannik are on a different level.

Last question: Venus Williams is still going strong at 45 years old. Can tennis fans count on you playing another 15 years?

No. They cannot (laughs). You will not see me for the next 15 years. I don't know how many more years you will see me, but it definitely will not be 15.

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