Ronald Acuna Jr. Becomes First MLB Player to Sign Kalshi Prediction Market Deal

Atlanta Braves outfielder Ronald Acuna Jr. has signed an advertising partnership with Kalshi, becoming the first MLB player to represent a prediction market platform.

Good to Know

• Kalshi introduced the partnership during Game 4 of the Braves playoff series against the Los Angeles Dodgers.
• Seven MLB teams already have prediction market partnerships with Kalshi, Polymarket or Novig.
• MLB prohibits players from trading contracts tied to league events, despite growing commercial ties with prediction markets.

Kalshi Builds on MLB Team Deals

Baseball trading volume on Kalshi has grown 36-fold year over year, according to the company. The platform already has agreements with the Atlanta Braves, Boston Red Sox, Los Angeles Dodgers, San Diego Padres and San Francisco Giants.

Meanwhile, Novig partnered with the New York Mets in July, before Polymarket secured a deal with the New York Yankees.

However, MLB maintains restrictions on player participation in prediction markets. Commissioner Rob Manfred and the Major League Baseball Players Association previously warned players against trading contracts involving league-sanctioned events.

Kalshi also faces an ongoing regulatory dispute over sports event contracts. State gambling regulators argue that prediction market operators need sports betting licenses, while Kalshi maintains that federal oversight through the Commodity Futures Trading Commission covers its activities.

The new agreement brings Acuna into a growing group of athletes promoting prediction markets, including Lionel Messi, Giannis Antetokounmpo and Bryson DeChambeau. Rival Polymarket has also worked with LeBron James, Eli Manning and Derek Jeter.

Earlier this week, San Antonio Spurs star Victor Wembanyama ruled out ever promoting a sports betting company, drawing a clear line between gambling brands and the companies he wants to represent.

In the new commercial, Acuna climbs out of an underground space beneath home plate and jokes, “There’s no place like under home plate, because I live here.”

The advertisement debuted Wednesday during the 4-1 loss to the Dodgers, which ended the Braves postseason.

Kalshi has not disclosed the financial terms or confirmed whether Acuna will feature in additional campaigns. The company has also reportedly discussed a broader partnership with MLB.