
The Athlete · Mission 50
Former tennis professional. Current coach. Chasing a Guinness World Record for two reasons — she loves the impossible challenge of it, and she loves tennis.

“I love the impossible challenge of it — and I love tennis enough to chase after this record.”
Sandra Alonso

In her words
So — I’m not going to tell you the story you’re probably expecting. I didn’t grow up dreaming about being a pro tennis player. I didn’t even get real training until I was sixteen. I wasn’t on a path to make it in the sport. I actually struggled, a lot, way more than I care to describe. From learning the game all the way to going pro. And for a while on that journey, I don’t think I actually believed I could keep going. Becoming a professional player kind of felt like a dream that got handed to me instead of one I picked. There were whole seasons where I just wanted a good enough reason to quit.
But that process taught me a lot about myself. Being on the court was, and still is, my favorite place in the world. I just wasn’t on the path I actually wanted to be on. Somewhere in all of it, tennis itself became mine — not an achievement, not the competition, not the career — but the game. I found that I love the sport of tennis. The early morning on the court, the final point as the lights turn off. The community. And, most of all, I think it’s the joy it gives me.
Now — that love for tennis, combined with the love for an impossible challenge, is what has led me to this attempt. I’m drawn to things that feel impossible, because of what it does to me while I’m in it — I stop thinking about everything else. And I get to feel that moment fully, doing the thing I love most.
On court
Training toward fifty.



Mission 50
It will take our community to achieve this mission.
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Fifty matches take more than one athlete. Here’s how to help.
Ball crew, court operations, record support and more. The attempt runs on people who show up.
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