San Diego Padres infielder Tucupita Marcano is facing a potential lifetime ban for betting on baseball after Major League Baseball received information that he wagered on games involving the Pittsburgh Pirates when he was with the team last season, sources confirmed to ESPN on Monday.

Marcano, 24, has yet to be formally penalized, but MLB Rule 21 explicitly states that a player who bets on games involving his own team is subject to a lifetime ban. Marcano tore an ACL last year and was on the injured list when he allegedly placed the bets, which were flagged by a sportsbook and reported to the league, according to sources.

The potential ban of Marcano comes in the wake of the NBA handing down a lifetime penalty to Toronto Raptors forward Jontay Porter for disclosing confidential information to bettors, limiting his participation in at least one game and betting on NBA games while playing in the G League.

Four other minor league players are facing potential discipline for gambling as well, sources told ESPN. Even if a player in the minor leagues is on a team's 40-man roster, he would face a one-year suspension for gambling on major league games, according to Rule 21.

The Wall Street Journal first reported the looming discipline for all five players.

As pervasive as gambling in sports has become, it is particularly sensitive in baseball, a sport whose hit king, Pete Rose, remains banned for gambling, and whose championship series was thrown in 1919 by the Chicago White Sox. Los Angeles Dodgers superstar Shohei Ohtani's former interpreter, Ippei Mizuhara, has indicated he plans to plead guilty to federal felony charges after admitting he had stolen money from Ohtani to pay off gambling debts.

MLB continues to investigate Ohtani's former teammate with the Los Angeles Angels, David Fletcher, for betting on sports with the same illegal bookmaker who took wagers from Mizuhara, according to ESPN's Tisha Thompson.

Marcano's case, about which MLB and the MLB Players Association continue to discuss the ultimate discipline, would represent the first direct penalty for a player betting on baseball since Rose. In 2015, Miami Marlins right-hander Jarred Cosart was fined for placing bets not on baseball but with an illegal bookmaker.

Since the Supreme Court's 2018 ruling that began the spread of legal betting in the U.S., 12 NFL players, an assistant coach and an undisclosed number of league personnel have been suspended for violating the gambling policy, in addition to Porter's banishment from the NBA.

MLB and the MLBPA declined comment, as did Marcano through his agent. Pirates senior vice president of communications Brian Warecki told ESPN: "We are aware of the matter that's under investigation and are fully cooperating. We will refrain from further comment at this time."

In a statement, the Padres said: "We are aware of an active investigation by Major League Baseball regarding a matter that occurred when the player in question was a member of another organization and not affiliated with the San Diego Padres. We will not have any further comment until the investigative process has been completed."

Marcano rejoined the Padres this winter as a waiver claim after they had sent him to Pittsburgh at the 2021 trade deadline in a trade for infielder Adam Frazier. In 149 career games, Marcano hit .217/.269/.320 with five home runs and seven stolen bases in 447 plate appearances.

ESPN's David Purdum contributed to this report