Ronald Acuña Jr. has become the first MLB player to sign with Kalshi, according to The Athletic, giving the prediction market a high-profile baseball face just as its push into the sport keeps accelerating.
A Kalshi commercial featuring the Atlanta Braves outfielder aired Wednesday night during Game 4 of the Braves’ National League Division Series against the Los Angeles Dodgers. Los Angeles won that game 4-1, clinched the best-of-five series 3-1, and ended Atlanta’s season.
The arrangement adds an individual endorsement from Acuña, a former National League MVP, to Kalshi’s existing partnership with the Braves.
It also lands at a moment when Kalshi has been making a heavier move into baseball. Less than two months ago, the company announced partnerships with five MLB clubs: the Braves, Boston Red Sox, Dodgers, San Diego Padres and San Francisco Giants. Kalshi is also reportedly in talks with MLB on a leaguewide agreement.
The Mets and Yankees were the first MLB teams to connect with trading platforms, with New York partnering with Novig and Polymarket, respectively.
Acuña is not the first active pro athlete to get involved with a prediction market. Earlier this year, golfer Bryson DeChambeau became the first to align with Kalshi, and he was followed by NBA star Giannis Antetokounmpo and Inter Miami forward Lionel Messi.
Still, The Athletic pointed out that Acuña’s deal could face more scrutiny than those other agreements. That’s because of MLB’s long relationship with gambling and the league’s history of trying to keep players away from wagering issues and game fixing.
Kalshi itself has also drawn attention through state-level fights over sports event contracts, including a $3 million push against state prediction market rules that RG.org reported on this week.
Prediction markets like Kalshi are regulated federally, while U.S. sportsbooks are licensed state by state.
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