The Major League Baseball Players Association is investigating agent Yasser Mendez after at least one player accused him of financial misconduct related to investments Mendez solicited for a baseball academy that he owns, according to MLB sources and documents reviewed by The Athletic.

In a grievance filed with the MLBPA last August, Philadelphia Phillies outfielder Johan Rojas alleges that in 2019 and 2022, when Rojas was a minor league player and represented by Mendez, the agent convinced him to take out two advances against future big league earnings totaling $875,000. Mendez then persuaded him to invest more than $450,000 in 4Pro, Mendez’s Venezuelan-based baseball academy, with promises of lucrative returns substantially more than the 25 percent Rojas was forfeiting in future earnings.

“That advice was intentionally, recklessly, or negligently wrong for Rojas,” according to the grievance, a copy of which was obtained by The Athletic.

Rojas also alleges that Mendez told him that some of the money he gave to him to invest in 4Pro would be used to cover Rojas’ tax liabilities, but the grievance states that Mendez underpaid Rojas’ taxes in 2020 and didn’t pay them at all in 2022.

Mendez was employed by Rep 1 Baseball, which is also listed in the grievance, at the time of the transactions. In 2023, Rep 1 Baseball announced it had been acquired by Klutch Sports Group. Jon R. Fetterolf, a lawyer for Klutch, said in an emailed statement: “Neither Klutch nor any of its employees had knowledge of the alleged conduct described in this article, said to have occurred long before the individual at issue was employed by Klutch.” Asked specifically if Mendez was still with Klutch, Fetterolf said Mendez was terminated in 2024. Chris Koras, the former COO of Rep 1 and now head of Klutch’s baseball division, was also named in the grievance and declined to comment beyond Fetterolf’s statement.

Mendez did not respond to multiple requests for comment. Rojas, through his lawyer, Michael Strauss, declined to comment. Strauss also declined to comment.

Andrew Latack, another attorney representing Klutch, Rep 1 Baseball and Koras, accused Rojas and Strauss of “an unsuccessful eight-month effort to extort Klutch out of $7.5 million” in a response to the grievance sent to the MLBPA. The response stated that Mendez “discouraged Rojas from taking any payments against his future earnings and that “Rojas voluntarily and eagerly participated in the investments.”

Still, the agency said in its response that Mendez transferred $465,123.24 to Rojas in January 2024.

The MLBPA declined to comment on the investigation or respond to a half-dozen questions from The Athletic, including whether Mendez was still an MLBPA-certified agent, as stated on Mendez’s Instagram account. An MLB source said Mendez is still listed in the MLBPA’s agent database.

At least one other player also entered into agreements with Mendez to invest in his academy, according to MLB sources. Yankees infielder Oswald Peraza took out multiple loans against future earnings while being represented by Mendez and invested some of that money in Mendez’s academy, according to sources briefed on the matter but not authorized to speak publicly. It’s unclear if Peraza’s transactions with Mendez, which sources believe may be bigger than Rojas’, are part of the MLBPA’s probe.

Rojas and Peraza both left Mendez and Rep 1 Baseball/Klutch in 2023. Peraza’s current agent, Dan Lozano (MVP Sports Group), said his client would not comment on the matter.

Future earnings agreements like the ones Rojas and Peraza signed have become a common – and occasionally controversial – part of minor-league baseball, one that has disproportionately impacted Latin players. Athletes can receive up-front payments in exchange for a percentage of their pre-tax income if they reach the big leagues. If a player doesn’t make it, they don’t have to repay the money. By being in the big leagues, both Rojas and Peraza are on the hook for more than 20 percent of their pre-tax earnings.

In January 2016, the same month that Big League Advance, one of the firms that Rojas used, was founded, the MLBPA sent a confidential memo to player agents warning that “the future earnings BLA is seeking are significant” and agents should “proceed with caution.”

Last week, star Padres outfielder Fernando Tatis Jr. sued Big League Advance in San Diego County Superior Court, alleging the company locked him into “an unlawful and exploitative arrangement.” In 2017, when Tatis was a teenage minor-league prospect, BLA gave him $2 million in exchange for 10 percent of his future earnings. Tatis is in the midst of a 14-year, $340 million contract with the Padres. He owes BLA 10 percent of his earnings as long as he’s in the big leagues.

On Feb. 7, 2025, the MLBPA sent an email to all certified agents, making changes to agent regulations effective as of Jan. 1. The first change prohibits loans from players to agents. The second clarifies and emphasizes existing rules against agents offering compensation directly or indirectly to a player.

Mendez has operated a baseball academy under a variety of names during the last decade, including the Yasser Mendez Professional Baseball Academy, the International Baseball Company and sometimes a combination of the two. He registered the 4Pro International Baseball Academy in May 2018, listing the address as a house in Orlando. Weeks later, Mendez announced he took a job with Rep 1 Baseball, calling it “one of the most important Baseball Agencies in the world,” and hashtagging Koras’ name.

In August 2018, MLB announced a Latin America trainer partnership program – encouraging safe and ethical practices of developing young talent – that included Mendez and 4Pro. The academy is located in Valencia, Venezuela, at the 4ProCity sports complex. That facility’s Instagram page identifies it as “By Yasser Mendez.” A court filing earlier this year said Mendez owns 90 percent of the shares in the Venezuelan company behind the academy. Mendez is still listed on MLB’s site as part of its “Trainer Partnership Program.”

(Photo of Phillies’ Johan Rojas: Rich Storry / Getty Images)