Major League Baseball has reportedly proposed a 154-game regular season and an expanded postseason, according to Tim Brown of Yahoo Sports. 

The proposal includes a one-month delay to the start of the season amid the COVID-19 pandemic and an extension to the calendar by one week. The MLB Players Association is reportedly considering the offer. 

However, Bob Nightengale of USA Today reported the MLBPA is expected to reject the offer on Monday.

Brown added that the players would be paid their full salaries if the season went the full 154 games, and that the MLBPA had previously rejected the expanded postseason. 

Buster Olney of ESPN later reported that spring training would start on March 22 under the proposal, with Opening Day taking place on April 28. The postseason would carry over into November, per Olney.

Joel Sherman of the New York Post broke down why the union might reject this offer and how the two sides remain far apart in a comprehensive Twitter thread:

Or as baseball writer Craig Calcaterra put it, the MLB's offer amounts to: "We give you a thing you already have in exchange for a thing that is INSANELY valuable to us and probably hurts you. Whaddaya say?"

The players have a few reasons for rejecting an expanded postseason. For one, there is the fear that more teams getting into the postseason could make owners less inclined to spend in free agency, since getting into the playoffs will be easier. 

If you think you can sneak into an expanded playoff, why spend big for that star player who would have potentially put you over the top in the past system? That, in turn, could drive down spending across the board. 

The other concern is that the owners and MLB receive the postseason television money, per Calcaterra, while the players get the "get a share of the postseason gate." So an expanded postseason almost exclusively benefits MLB's owners and the league when it comes to negotiating those television rights with broadcasters. 

Last year's negotiations for a shortened season amid the coronavirus pandemic between the players and owners was protracted and heated. Repeating that scenario at least doesn't appear to be an option:

With one more year under the current CBA, the current plan is to begin baseball on that April 1 date. The ongoing complications of the coronavirus have made that start date less than ideal. But if the two sides can't agree on an alternative plan, baseball will remain on the current trajectory to start on April 1.