Major League Baseball commissioner Rob Manfred told ESPN on Monday he's "not confident" there will be a 2020 baseball season and that "as long as there's no dialogue" with the MLB Players Association, "that real risk is going to continue."

In a conversation with Mike Greenberg for ESPN's "The Return of Sports" special, Manfred walked back comments made to ESPN last week, when he said "unequivocally we are going to play Major League Baseball this year" and pegged the likelihood at "100 percent."

"I'm not confident. I think there's real risk; and as long as there's no dialogue, that real risk is gonna continue," Manfred said when asked if he was confident there would be a season.

The chance that there will be no season increased substantially Monday when the commissioner's office told the players' association it will not proceed with a schedule unless the union waives its right to claim management violated a March agreement between the feuding sides, a source told ESPN, confirming a report by the Los Angeles Times.

Manfred was asked about what the talks are doing for the optics of MLB while the country has been shut down by the coronavirus pandemic and only recently starting to reopen.

"It's just a disaster for our game, absolutely no question about it. It shouldn't be happening, and it's important that we find a way to get past it and get the game back on the field for the benefit of our fans," he said.

Manfred said the MLBPA's "decision to end good-faith negotiations" and the need for an agreement with the union on health and safety protocols "were really negative in terms of our efforts."

"The owners are 100 percent committed to getting baseball back on the field," Manfred said. "Unfortunately, I can't tell you that I'm 100 percent certain that's gonna happen."

On Saturday, a day after MLB delivered a return-to-play proposal that called for a 72-game season and guaranteed 70% of players' prorated salaries (with a maximum of 83%), MLBPA lead negotiator Bruce Meyer said in a letter to MLB deputy commissioner Dan Halem: "Given your continued insistence on hundreds of millions of dollars of additional pay reductions, we assume these negotiations are at an end."

MLBPA executive director Tony Clark followed with a statement asking the league to use its right from the sides' March 26 agreement to set a schedule, saying: "It unfortunately appears that further dialogue with the league would be futile. It's time to get back to work. Tell us when and where."

Manfred said he believes the union intended to file a grievance that the league had not fulfilled its obligation under the March 26 agreement to play the most games possible, which he deemed a "bad-faith tactic."

Cincinnati Reds pitcher Trevor Bauer responded to Manfred's comments, calling them a "bluff" in a series of tweets.

You're holding a losing hand. Unfortunately, it's a losing hand for everyone involved, not just you. There's some saying out there about not killing the goose that lays the golden eggs. Check it out on the ole google machine. It's worth knowing.

— Trevor Bauer (@BauerOutage) June 15, 2020

"I had been hopeful that once we got to common ground on the idea that we were gonna pay the players' full prorated salary, that we would get some cooperation in terms of proceeding under the agreement that we negotiated with the MLBPA on March 26," Manfred told ESPN. "Unfortunately, over the weekend, while Tony Clark was declaring his desire to get back to work, the union's top lawyer was out telling reporters, players and eventually getting back to owners that as soon as we issued a schedule -- as they requested -- they intended to file a grievance claiming they were entitled to an additional billion dollars. Obviously, that sort of bad-faith tactic makes it extremely difficult to move forward in these circumstances."

Manfred was one of six professional sports commissioners to be interviewed for the special, which will air Monday at 9 p.m. ET on ESPN.