Last December, MLB shared a memo warning the players about investing in the prediction market business. But it took MLB just three months to backtrack from its previous stance. They have now got into a deal with one of the country’s leading prediction-market companies, Polymarket. This decision promises a massive payday for the league. But fans are seemingly left unamused by how MLB commissioner Rob Manfred backtracked from his previous stance.

“Major League Baseball is getting into the prediction-market business through a multi-year deal with Polymarket,” Front Office Sports reports. “Under the deal, Polymarket will become the exclusive prediction-market partner of MLB and will be the only platform allowed to use team logos and marks.”

The deal between MLB and Polymarket is rumored to be around $300 million for three years. Under the deal, Polymarket would have access to official logos, and fans across all 30 teams could invest based on their prediction. And MLB is the latest pro league to join the prediction market bandwagon. MLS, UFC, and NHL have already signed a deal with Polymarket.

But here’s the catch!

In the last few years, the prediction market industry has witnessed explosive growth, especially in the sports market. It is projected to reach $10 billion by 2030, up from a $3 billion annual run rate in early 2026. So with the industry steadily becoming mainstream from being a niche, pro leagues are expectedly lining up for a deal. But MLB’s traditional stance is what’s making all the news.

“Late in the 2025 season, Major League Baseball sent a memo directly prohibiting its players from engaging with baseball event contracts on Kalshi, Polymarket, and other prediction markets,” Front Office Sports reported back in December. Even Manfred emphasized how their “No. 1 priority is to protect the integrity of the game.”

Well, fans wonder how MLB would maintain its integrity now, post their deal with Polymarket. “I hope that it goes without saying that our primary concern, always first in our minds, is protecting the integrity of the game,” Manfred said. “I think in today’s world, it is really important not to be chasing developments but to try to be involved and in front of those developments because our world is so fast-moving.”

So, MLB is trying to accept the evolution it was once infamous for not accepting, but also not sacrificing integrity. However, they just had a deal with the same $9 billion brand that was closed for the U.S. customers till last year.

Polymarket did not allow U.S. customers for a significant period following a 2022 settlement with the Commodity Futures Trading Commission (CFTC), which accused the company of operating an unregistered platform. They had to pay a $1.4 million fine for the same.

Just in November, the CFTC granted Polymarket an Amended Order of Designation, allowing it to operate as a regulated exchange.  But MLB fans? They are not impressed.

MLB’s deal with Polymarket has left the fans fuming

Fans are wondering about what made MLB backtrack from its traditional stance on sports betting. “They spam betting companies all over the games, then treat players as the problem when they fall into gambling…. lol,” one fan said. “Rob Manfred is BRAINDEAD. Only going to make the gambling issue worse. They are going to kill off the MLB…,” another added.

In recent years, MLB has extensively embraced sports betting companies. They already got into partnership with companies like FanDuel and DraftKings. But while this increased revenue and fan engagement, it is a significant deviation from what MLB once stood for. Before 2018, sports betting advertisements were also banned in the ballparks.

Currently, more sports betting companies are investing in MLB, and Polymarket is opening its market prediction business. So, fans are skeptical about whether MLB could be any stricter about the game’s integrity.

“And they won’t put Pete Rose into the Hall of Fame is a tragedy,” a user remarked. “So why are the Guardians players in trouble now?” another one asked.

Just last year, MLB lifted Reds’ legend Pete Rose’s lifetime ban posthumously. Rose was banned for being actively involved in sports betting, and he is yet to get his place in Cooperstown despite having a record of 4,256 hits. Most recently, Guardians’ Lusi Ortiz and Emmanuel Clase were banned last year for the same allegation.

So, fans wonder, if MLB is embracing market prediction and betting as legal, why would the players be punished? “Then we all put on our shocked faces when players get caught “predicting” games,” one fan agrees.

As MLB chases new revenue streams, it risks alienating a fanbase that sees the league compromising its core principles for profit.