Atlanta Braves superstar Ronald Acuña Jr. has become the first Major League Baseball player to sign a promotional partnership with prediction-market platform Kalshi. The agreement marks another milestone in Kalshi’s expansion into professional sports, bringing one of baseball’s most recognizable athletes into the rapidly growing event-contract industry.
Acuña Makes MLB History With Kalshi Partnership
Ronald Acuña Jr. officially entered the prediction-market industry through a new endorsement agreement with Kalshi.
The partnership was highlighted by a commercial featuring Acuña that aired on October 7, during Game 4 of the Atlanta Braves’ National League Division Series against the Los Angeles Dodgers.
The agreement makes Acuña the first MLB player to promote a prediction-market platform, extending Kalshi’s marketing strategy beyond professional sports organizations and into individual athlete partnerships.
Financial terms of the agreement have not been publicly disclosed.
Kalshi Already Has Partnerships With Five MLB Teams
Acuña’s agreement follows Kalshi’s August announcement of partnerships with five Major League Baseball organizations.
Those teams include:
Atlanta Braves
Boston Red Sox
Los Angeles Dodgers
San Diego Padres
San Francisco Giants
The partnerships include stadium advertising, social media campaigns, digital promotions and fan experiences.
Kalshi reported that baseball-related trading volume on its platform had increased 36 times year over year when it announced the team agreements.
Other prediction-market platforms have also entered professional baseball. The New York Yankees partnered with Polymarket, while the New York Mets partnered with Novig.
Kalshi has reportedly been discussing a potential leaguewide partnership with MLB, although no such agreement has been announced.
Kalshi Expands Its Athlete Endorsement Strategy
Acuña joins several internationally recognized athletes who have entered promotional relationships with Kalshi.
The platform’s athlete partnerships include:
Bryson DeChambeau — Professional golf
Giannis Antetokounmpo — NBA basketball
Lionel Messi — International soccer
Ronald Acuña Jr. — Major League Baseball
These partnerships give Kalshi access to major sports audiences as the company competes for users in the growing prediction-market sector.
Unlike traditional sportsbooks, Kalshi offers event contracts that allow customers to trade positions based on the outcomes of real-world events, including sports competitions, elections and economic developments.
MLB Gambling Restrictions Raise Questions
Acuña’s agreement arrives during an ongoing debate over how prediction markets should operate within professional sports.
MLB players are prohibited from trading contracts tied to baseball outcomes, even though teams and individual athletes may enter certain promotional relationships with prediction-market companies.
In 2025, Major League Baseball and the MLB Players Association issued a joint warning reminding players that risking money on baseball-related outcomes could violate league rules.
The issue has attracted additional attention following the November 2025 indictments of Cleveland Guardians pitchers Emmanuel Clase and Luis Ortiz over allegations involving manipulated pitch outcomes and illegal wagering.
Those allegations are separate from Acuña’s endorsement agreement, and there is no indication that Acuña has violated MLB’s gambling policies.
However, his partnership highlights the distinction between promoting a prediction-market platform and personally trading on baseball events.
Prediction Markets Face Growing Regulatory Challenges
Kalshi operates as a federally regulated derivatives exchange under the oversight of the Commodity Futures Trading Commission.
However, the legal status of sports-related event contracts remains disputed.
Several state regulators have challenged prediction-market platforms, arguing that certain sports contracts resemble gambling products that should fall under state gaming laws.
New York’s attorney general has also pursued legal action against Kalshi and Polymarket, alleging that their sports-related offerings violate state gambling requirements.
Prediction-market companies maintain that their event contracts are federally regulated financial products.
The outcome of these disputes could influence how platforms market sports contracts and structure partnerships with leagues, teams and athletes.
Atlanta Braves Become Part of Prediction-Market Expansion
For Atlanta, Acuña’s partnership adds another connection between the city’s professional sports industry and emerging financial technology.
The Braves were already among the first five MLB teams to partner with Kalshi in August. Acuña’s individual agreement now extends that relationship to one of the franchise’s biggest stars.
The development also demonstrates how prediction markets are moving beyond cryptocurrency and financial trading communities into mainstream sports and entertainment.
As platforms compete for new customers, partnerships with recognizable athletes offer opportunities to introduce event contracts to audiences who may have little previous experience with prediction markets.
Acuña’s agreement represents a first for Major League Baseball, while also bringing greater attention to the unresolved regulatory questions surrounding sports prediction markets.
