Major League Baseball has sent a new proposal to the MLB Players Association, sources told ESPN's Jeff Passan on Wednesday.

No deal is done, but with MLB commissioner Rob Manfred and MLBPA executive director Tony Clark having met recently, this is seen as significant progress considering where the parties were a few days ago.

MLB has made three proposals to start the 2020 season and the players' union two, and the sides remain about $1 billion apart in guaranteed salary. Players were set to earn $4 billion in salaries before the coronavirus outbreak began.

The union cut off talks Saturday, a day after MLB's last proposal, and said additional negotiations were futile. Players told MLB to unilaterally set the schedule, but Manfred said the league would not while there was a threat of a grievance.

On Monday, Manfred told ESPN he was "not confident" that a 2020 baseball season would be played, walking back previous comments that "unequivocally, we are going to play Major League Baseball this year" and pegging the likelihood at "100%."

"I'm not confident," Manfred told ESPN's Mike Greenberg. "I think there's real risk, and as long as there's no dialogue, that real risk is going to continue."

The sides reached a deal March 26 in which players agreed to prorated salaries, part of an agreement that included a guarantee of service time even if no games are played this year.

Teams say they need more pay cuts to afford to play in empty ballparks. Players say they will not accept additional salary reductions.

On Saturday, the 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."

Clark followed with a statement asking the league to use its right from the 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."

Numerous players echoed Clark on Monday in response to Manfred, tweeting, "Tell us when and where."

Manfred said in Monday's interview that 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."

The Associated Press contributed to this report.