When the N.F.L. on Thursday announced that three players had been found to have bet on football, the penalties came down with characteristic harshness: indefinite suspensions which can only be appealed after a full season.

It was the second such set of gambling penalties levied this off-season, after the league in April invoked the same suspension against three players who had bet on N.F.L. games.

The suspensions, punitive by nature, were also a warning to other pros tempted by the pervasive opportunities to bet on football. But, critics say, the harsh punishment is dissonant with the league’s business partnerships with betting companies, which brought the league more than $1 billion in 2022.

On Thursday, the N.F.L. suspended Isaiah Rodgers and Rashod Berry of the Indianapolis Colts and free agent Demetrius Taylor through at least the 2023 season for betting on N.F.L. games. Shortly after the announcement, the Colts released Rodgers and Berry.

“The integrity of the game is of the utmost importance,” Chris Ballard, the team’s general manager, said of the decision.

His language echoed that of Jeff Miller, the league’s executive vice president for communications, public affairs and policy, who in the aftermath of the April suspensions told reporters: “The integrity of the game has to be held at such a high standard that there’s no tolerance for those sorts of behaviors.”

The N.F.L. began its embrace of sports gambling after the Supreme Court in 2018 struck down a ban that kept betting out of most states. Since then, sports betting has emerged as a lucrative source of revenue for the league as has gambling spread. In 2021, the N.F.L. partnered with DraftKings, FanDuel and Caesars Entertainment on agreements reportedly worth nearly $1 billion collectively.

After a long avoidance of Las Vegas and its casinos and sports books, the Super Bowl will be held there in February, nearly seven years after team owners approved the Raiders’ relocation there.

The recent suspensions show the league’s struggle to draw a line in its acceptance of gambling, said Bob Boland, a sports law professor at Seton Hall and the former athletics integrity officer at Penn State.

“The idea that sports betting is part of our product, we advertise in our broadcasts and where it was once something we recoiled from, now it’s something we kind of embrace, but not for you as a player,” Boland said in an interview. “That’s the complicated question of that and it sends mixed messaging.”

Though the league’s gambling policy is detailed in Appendix A of the N.F.L.’s collective bargaining agreement — and is included on every player contract — players of late have expressed misgivings about the prohibitions.

“I understand rules are rules, But I can risk my life so that my team wins but I can’t risk 1k on my team winning,” the Patriots cornerback Jonathan Jones wrote in a Twitter post, referring to the suspensions.

When the Lions receiver Jameson Williams was hit with a six-game suspension for betting on other sports while in a team facility, he claimed he was not aware of the N.F.L.’s policy.

The league has said it will make the policy a point of emphasis, visiting teams to highlight the fine points of the rules on gambling and mandating that rookies attend informational sessions. But levying strict discipline has so far been football’s most visible attempt to ensure the competition on the field is fair and uninfluenced, a key to maintaining consumer confidence.

You want to create the interest so that the last shot, the last kick, the last pass is always subject to chance and human endeavor. It’s why we love them, to a degree,” Boland said. “The fact that they would be fixed or that the outcome was created would immediately draw interest away.”

But by allowing the potential for reinstatement for players who bet on football, the N.F.L. stopped short of the zero-tolerance policy that has been a bedrock in Major League Baseball since the “Black Sox” scandal in 1919, when the Chicago White Sox were accused of throwing the World Series.

Instead, the N.F.L.’s indefinite suspensions, with the possibility of return, serve as an effective ban on fringe players while leaving the door open for stars who bet on football to return to play.

Calvin Ridley, who was suspended for the 2022 season for gambling on the sport, can return once he has served his suspension. But for less impactful contributors like Rodgers and Berry, a path back to football is less clear.

Indefinite suspensions aren’t a recent solution in the N.F.L. In 1947, Commissioner Bert Bell indefinitely suspended Frank Filchock and Merle Hapes of the New York Giants for “acts detrimental to the N.F.L. and pro football” after they were allegedly offered bribes to fix that year’s championship game, though neither player accepted. Filchock’s suspension was lifted in 1950, and he played in only one more game. Hapes’s suspension was lifted after seven years, and he never played another down.

That scandal compelled Bell to expand the N.F.L.’s betting surveillance, including by hiring former F.B.I. investigators to keep tabs on league officials and gamblers alike. Team owners also granted him the unilateral authority to impose a lifetime ban on anyone involved in gambling on the sport. In 1963, Commissioner Pete Rozelle suspended two players for 11 months for betting, despite finding no evidence that they tried to influence the outcome of a game.

The next player penalties for betting on football came in 2019, when the Arizona Cardinals cornerback Josh Shaw was suspended through the end of the 2020 season for betting on N.F.L. games. (Shaw was reinstated in 2021 but has not played in an N.F.L. game since.)

The recent spate of gambling infractions may eventually force the league to consider harsher punishment, an outcome that would need to be agreed upon by the N.F.L. players’ union. The volume and star status of player bettors, LeRoy said, could give both sides incentive to go further to protect confidence in football games.

“Let’s just say, hypothetically, that the league really digs into this kind of investigating and they find that 100 or more players are gambling,” he said, “so that you would have a massive disruption of team rosters. That’s the kind of thing that, I would think, would induce the parties to come to the table and bargain over this.”