MLB’s past few seasons have been plagued by a spate of gambling scandals.

In April 2024, authorities arrested Ippei Muzihara, the interpreter for Los Angeles Dodgers superstar Shohei Ohtani, on suspicion of illegally transferring more than US$16 million from Ohtani’s bank accounts to pay a bookie. Muzihara pleaded guilty in February 2025.

Two months later, MLB suspended four minor leaguers for violating the league’s sports betting rules. The league also issued a lifetime ban to San Diego Padres utility infielder Tucupita Marcano – the first active player in a century to receive one due to gambling.

The following season, MLB placed Cleveland Guardians All-Star closer Emmanuel Clase and starting pitcher Luis Ortiz on indefinite leave after suspicions emerged that they’d rigged pitches to help gamblers win bets. In November 2025, both were federally indicted, and each has pleaded not guilty.

But if you thought that MLB might ease up on its embrace of sports betting ahead of the 2026 season, you would be mistaken.

On March 19, 2026, MLB announced a new partnership with Polymarket. The world’s largest prediction market, Polymarket allows users to buy shares on the outcomes of future events – like betting – but with probabilities instead of odds.

For most of baseball’s history, formal affiliation with any form of gambling was inconceivable. That has changed under current MLB Commissioner Rob Manfred who, since the start of his tenure in 2015, has embraced gambling and prediction markets as they’ve become legalized in the U.S.

I’ve researched and written about the league’s abrupt reversal from anti-gambling crusader to sports gambling partner, and how Manfred has justified this pivot to players, fans and the media.

The about-face is even more jarring when you consider the fact that the commissioner position itself was created in the wake of the 1919 “Black Sox” scandal.

During that infamous episode, Shoeless Joe Jackson, Eddie Cicotte, Chick Gandil and five of their teammates on the Chicago White Sox conspired to intentionally lose the World Series, forcing the sport to break from the gambling culture that helped fuel its rise.

With baseball’s integrity in doubt, the league chose an outsider – Illinois federal judge Kenesaw Mountain Landis – as its first commissioner.

“We have got to have a higher standard of integrity and honesty in baseball than in any other walk of life,” Landis said upon accepting the job. “And we are going to have it.”

Thus began baseball’s century of resisting – and punishing – any whiff of gambling.

In 1947, Landis’ successor, Happy Chandler, suspended Brooklyn Dodgers manager Leo Durocher, in part, for his ties to gamblers.

Bowie Kuhn, who served as commissioner from 1969 to 1984, suspended All-Star pitcher Denny McLain in 1970 for his involvement with bookmakers. He later banned baseball greats Willie Mays in 1979 and Mickey Mantle in 1983 for working as casino promoters, though commissioner Peter Ueberroth reinstated them in 1985.

The most notorious post-Black Sox scandal involved all-time hits leader Pete Rose. In 1989, Ueberroth launched an investigation after hearing that Rose had bet on games while managing the Cincinnati Reds.

A. Bartlett Giamatti, who became commissioner later that year, banned Rose from the sport for life in 1989 at the conclusion of the investigation.

The next two commissioners, Fay Vincent and Bud Selig, consistently denied Rose’s appeals to be reinstated. In 2012, Selig described gambling as “evil,” adding that it “creates doubt and destroys your sport.”

From fantasy to reality

Manfred took the baton from Selig in 2015, just as daily fantasy sports were becoming more popular.

Daily fantasy sports players draft rosters of athletes competing that day, stake money and win cash prizes based on the athletes’ real-life performances. Sports leagues permitted daily fantasy sports, deeming them games of skill, not chance.

Even though daily fantasy sports operated in a legal gray area, Manfred inked a deal with DraftKings in April 2015 to make the fledgling brand MLB’s “Official Daily Fantasy Game.”

“The fantasy space,” Manfred explained at the time, “was really, really important to [MLB] in terms of engaging young people.”

Manfred took pains to distinguish these games from gambling, telling reporters in April 2015 that “there’s a line in the law. And we understand that line very carefully.”

But by the time the Supreme Court decided in 2018 to put the legalization of sports gambling in the hands of the states, Manfred described the league as a gambling authority that was “in a position to meaningfully engage and shape … what the new regulatory scheme looks like.”

Protecting integrity to enable prosperity

Much of MLB’s shift is in response to legal, technological and cultural forces beyond its control.

But there’s a difference between accepting the legality of gambling and actively promoting it, whether that’s through opening sportsbooks at stadiums like Wrigley Field or saturating game broadcasts with gambling advertisements.

Under Manfred, the league’s messaging can be summed up as follows: Gambling is happening whether we like it or not. By going all in on gambling, we can at least control what shape it takes and better shield the sport from those with ill intent.

It’s a bit convoluted, to say the least. But the scandals that have emerged have given Manfred opportunities to double down on the logic.

By giving exclusive data access to MGM Sportsbook, for example, the league claims it can detect and monitor suspicious behavior.

Manfred has said that baseball is “in a better position to know what’s going on today then we were in the old days when it was all illegal,” a position he credits to the league’s work with its gambling partners.

In this way, the league frames its gambling partnerships as protective – even as new scandals emerge.

Other trends have made fans and owners more receptive to gambling.

Baseball’s embrace of gambling and prediction markets – with their spreads, parlays and share prices – is unfolding at a time when people are more comfortable with the integration of data and technology. Rhetoric scholar Michael Butterworth calls this “the statistical frame” – the idea that the world is increasingly understood through data, whether it’s through polling results, blood oxygen levels and, yes, betting odds.

The game has also changed from the owners’ box. Fewer teams are being steered by local, civic-minded businesspeople. In their place are international investment groups and private equity firms that treat franchises as part of a broader asset portfolio. According to sports journalist Bruce Schoenfeld, the sports industry has come to resemble “a mutual fund that includes television and digital content, real estate, retail clothing, hospitality, catering and concessions.”

For a sport increasingly focused on return on investment and growth, a reunion with gambling was a natural next step for baseball. And it’s been a boon for the bottom line.

Baseball’s ‘best interests’

In conjunction with the Polymarket announcement, Manfred also signed a memorandum of understanding with the chairman of the Commodity Futures Trading Commission, reiterating that “protecting the integrity of the game on the field is our top priority.”

But what about the protection of the athletes themselves?

Baseball players have opened up about the threats they’ve been subjected to since gambling’s legalization.

“You hear it all, man,” Arizona Diamondbacks reliever Paul Sewald told USA Today. “You blow a save, you don’t come through, you get it all. … ‘You cost me all of this money. (Expletive) you. (Expletive) your family. I’m going to kill you and then kill your family.’”

Manfred has said that these developments are “a matter of concern to us that we take really seriously.”

It’s possible that MLB will return to an anti-gambling stance in the face of these mounting threats. But as annual revenues for sports betting soar toward US$20 billion, that’s a tough bet to make.

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