Katerina Siniakova teams up with Pete Wentz for charity match in San Diego

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From under the cork tree to onto the tennis court. Fall Out Boy rocker Pete Wentz joined Katerina Siniakova at the Cymbiotika San Diego Open on Thursday for a charity mixed doubles match to raise money for Rady Children’s Hospital.

It's the second year in a row that the tournament has hosted a charity mixed doubles match for the hospital, and featured Wentz.

Last year, Wentz teamed up with Aryna Sabalenka for the fundraiser, and this year, he and Siniakova were joined by "Survivor" host Jeff Probst.

Wentz is one of Hollywood's biggest tennis enthusiasts, and has been spotted over the years on the practice courts at the BNP Paribas Open and in the stands at the US Open.

In an interview withGQmagazine in 2021, the musician revealed that he first played the sport as a kid in the Chicago suburbs, but recommitted at age 35 when his oldest child started taking lessons. He's honed his game with coach Chris Crabb, who's also an actor and has a private court in Los Angeles. Crabb has taught other stars including Dakota Fanning, Zach Braff and Steve Carrell. Last year, Wentz told tennis.com's Joel Drucker that Sabalenka and Nick Kyrgios are among his favorite current pros, and that he was inspired by Andre Agassi.

"Some days I'm a complete park rat and I'll play, like, six hours a day," he said. "When I play tennis, when it's going well, that's all I think about. I don't think about anything else. That's a nice feeling."