NORTH PORT, Fla. — With much of baseball in open revolt over his handling of the Houston Astros' sign-stealing scandal, MLB Commissioner Rob Manfred on Sunday defended his decision not to punish individual players involved in the scheme, acknowledged the option of vacating the Astros' 2017 World Series title was on the table at one point and said MLB was making plans to severely restrict players' access to in-game video feeds for the 2020 season.

At a Grapefruit League Media Day news conference at the Atlanta Braves’ new spring training facility, Manfred, with the fallout from the Astros’ scandal threatening to overshadow the opening of camps across Florida and Arizona, said the stain on individual players from the scheme’s exposure was itself a form of punishment.

“One thing I do take issue with [is] the notion that anybody in the Houston organization escaped without punishment,” Manfred said. “If you look at the faces of the Houston players as they’ve been out there publicly addressing this issue, they have been hurt by this. They will live with questions about what went on in 2017 and 2018 for the rest of their lives.”

When MLB launched its investigation of the Astros’ scheme — which found players, in 2017 and 2018, used a center field camera and a video monitor to steal signs from opposing catchers, then transmitted those signs to their hitters by banging on a trash can — it decided to grant players immunity in exchange for their testimony, in part to avoid legal conflicts with the MLB Players Association that represents players. While Astros manager A.J. Hinch and general manager Jeff Luhnow ultimately lost their jobs, and the team was fined $5 million and docked four premium draft picks, players went unpunished.

However, Manfred indicated there had been productive talks with the union about ensuring future transgressions by players would be dealt with more harshly.

“I understand when people say the players should have been punished. I understand why people feel that way, because [the Astros] did not do the right thing,” Manfred said. “In [a] perfect world, if I could have found all the facts without granting immunity, I would have done that. . . .

“We’re talking to the MLBPA about . . . what should be done about these sorts of issues on a go-forward basis, and exactly how we should deal with players in these types of situations, so yes, I could envision it being different in the future.”

Manfred also for the first time acknowledged extensive internal discussions about vacating the Astros’ 2017 championship, which would have been an unprecedented step for the sport. Instead, Manfred, a self-professed “precedent guy,” said he decided to let fans decide for themselves how to regard the Astros’ now-tainted championship.

“Once you go down that road, as for changing the results on the field, I just don’t know where you stop,” he said. “. . . The 2017 World Series will always be looked at as different,” he said, “[and] whether or not you put an asterisk [next to it] or ask for the trophy back I don’t think makes that much of a difference.”

With the first spring training exhibition games just days away, the Astros are the subject of widespread and unprecedented public criticism this spring from opposing players and executives, and the organization’s bungled public apology — which Manfred, in an interview Sunday morning with ESPN, acknowledged was “not successful” — seemed to have only made things worse.

In addition to the criticism, there remains open speculation across the game that the Astros’ scheme continued into 2019, despite the investigation finding no evidence that it did. Specifically, second baseman José Altuve has been accused of wearing a buzzer under his jersey to signal pitches to him during the 2019 American League Championship Series, which he clinched with a walk-off home run against the New York Yankees in Game 6. Manfred said MLB investigated those claims and found no validity to them but acknowledged he could not be “100 percent sure” they were not true.

“The players were candid about 2017 and the fact they violated the rules in 2017. They were . . . consistent about the fact that the rules were violated in 2018,” Manfred said. “And they were equally consistent, every single witness, in the denials about this buzzer allegation. In my own mind it was hard for me to figure out, given that they were immune, why they would be truthful, admit they did the wrong thing in ’17, admit they did the wrong thing in ’18, and then lie about what was going on in ’19.”

In the absence of punishment for Astros hitters involved in the scheme, some across the game have speculated that opposing pitchers would seek to impose their own form of justice by hitting the Astros intentionally with pitches. Manfred sought to quell such notions Sunday, saying he has conveyed to team personnel that “retaliation in-game by throwing at a player intentionally will not be tolerated, whether it’s Houston or anyone else.”

The Astros’ propensity for sign-stealing was an open secret across the game, with two executives telling The Washington Post they knew of 10 to 12 teams that had asked MLB to investigate the Astros for an illegal scheme. But it still took a whistleblower, former Astros and current Oakland Athletics pitcher Mike Fiers, going on the record with the Athletic in November for the scheme to be revealed and for action to be taken. Manfred said the earlier allegations were investigated but were limited by the lack of specific information provided by other teams.

“We had complaints from a variety of people about a variety of clubs, including the Astros, and in response to every one of those we undertook an effort to figure out whether we could verify the assertions that were made,” Manfred said. “[But] just to give you some context, usually those assertions took the form of, ‘We know they have our signs.’ It is hard to prove something when that is [all] you have.”

The league is wrapping up a separate investigation into illegal sign-stealing by the 2018 Boston Red Sox, which Manfred said should be completed by the end of the month. But when asked about allegations about and potential investigations into other teams, he declined to comment.

Manfred said the policy changes that were made in 2018 and 2019 regarding access to video monitors during games have been effective in “limiting this kind of behavior.” And he said MLB is in talks with the union to enact further restrictions on in-game use of video — such as when hitters go to their clubhouse to review their at-bats pitch-by-pitch before returning to the field.

“I think it’s really important to us to send a message to our fans,” Manfred said, “that not only did we investigate and punish but we altered our policies in a way to help make sure it doesn’t happen again.”