Serena Williams is always up for a challenge.
Watch Serena crash a tennis match between two guys playing on a public park court.
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The world No. 1 was out for a stroll with fiance Alexis Ohanian in San Francisco on Sunday night when she came across these two guys playing a friendly match at the Dolores Park courts, reports TMZ Sports.
"Oh my Goodness!" one of the men exclaims recognizing the Australian Open champion.
Serena, who grew up playing on public park courts in Compton, stepped up and asked to challenge the winner.
The 23-time Grand Slam champion took the court wearing black boots and gave both men a memory to last a lifetime as Ohanian joked "You already trash talking?"
A smiling Serena left the fans with this message: "The moral of the story is: You never know when I'm coming to a tennis court year you!"
Photo credit: TMZ