10:10am: The league and Union have formally announced the changes. A full rundown of the new rules is available, but here’s a more concise overview:

Effective Immediately

There will be no trades after July 31. August trade waivers have been eliminated, though players can still be placed on and claimed from outright waivers, as they would throughout the rest of the year.

All-Star voting will still be conducted by fans online, but the top three players at each position, in each league, will now participate in an All-Star Election Day. The top three vote-getters at each position, in each league, (top six in the case of outfielders) will receive bonus payments.

The Home Run Derby will now come with $2.5MM of prize money, including a $1MM prize for the winner.

The maximum number of mound visits per game will be reduced from six to five.

Commercial breaks between innings are reduced to two minutes in length for all games.

The MLB and MLBPA will form a “Joint Committee” to discuss further issues and rule changes.

Effective Beginning in 2020

The standard roster size in regular season games and postseason games will increase from 25 to 26 players. Beginning on Sept. 1, roster size will expand further to a 28-player maximum (as opposed to the current 40). A maximum number of pitchers will be designated by the Joint Committee. (Passan reported that the league has proposed no more than half a team’s players can be pitchers.)

Position players are only eligible to pitch in extra innings or when a team is leading or trailing by seven or more runs. Certain position players may be designated as “two-way players,” but to be eligible, they’ll need to have accrued at least 20 innings pitched and started 20 games as a position player/designated hitter in the current season or the preceding season (including at least three trips to the plate in each of those lineup appearances).

A pitcher must face at least three batters per appearance unless he is removed due to injury or the half-inning in which he is pitching ends before three batters have come to the plate.

The minimum length of stay for pitchers who are optioned to the minors or placed on the injured list will increase from 10 days to 15 days. This change is still “subject to input” from the newly formed Joint Committee.

March 14, 7:10am: Passan has several updates this morning, adding that there’ll be cash prizes in the annual Home Run Derby beginning in 2019, including $1MM to the winner, as an enticement for the league’s top talent to participate. Commercial breaks between innings are being shortened for a second time as well.

Pitchers will be required to face a minimum of three batters beginning in 2020, barring injury (previous reports on that possibility suggested that said ruling would also exempt cases in which a pitcher finishes an inning). More controversial issues among fans, including the implementation of a 20-second pitch clock and a universal DH, have been tabled for now but will continue to be discussed.

March 13: Major League Baseball and the MLB Players Association have reached an agreement on a series of changes regarding roster construction, per both Ken Rosenthal of The Athletic (subscription required) and Jeff Passan of ESPN. While it seems that this wave of agreed-upon changes will not technically impact actual in-game rules, the two sides have agreed to make July 31 a hard deadline for the completion of trades, thus doing away with the convoluted August waiver system. That change will go into effect for the 2019 season, and beginning in 2020, the standard roster size will expand from 25 to 26 (with a 13-pitcher maximum). September rosters, meanwhile, will shrink from 40 to 28 (with a 14-pitcher maximum).

As Passan details, the All-Star Game selection process will also be getting a facelift in 2019. Fans will still be permitted to cast votes online, but the top three players at each position will then be included in a newly implemented All-Star “Election Day” which figures to provide new avenues to marketing the game’s top talent both in mainstream media and via social media.

The precise manner in which the singular trade deadline will impact action on the summer trade market won’t be known for certain until we have multiple seasons of data, but from a distance it figures to heighten July trade activity. Contending clubs, one would imagine, will be forced to be more aggressive when seeking to acquire talent, while borderline teams who would previously have waited until mid- or late-August to sell off assets in a series of waiver claims will now be forced to make a decision much sooner. The idea is divisive among the GMs to whom Rosenthal spoke, but it seems that the Union’s hope is that pushing up the final date for in-season improvements will also prompt expected contenders to be a bit more aggressive in the offseason.

The broadest, most far-reaching development comes from Passan. As part of the recent agreement, both the league and the Union have already agreed to “imminently” begin discussing the labor issues that have been thrust to the forefront of the industry despite the fact that the current collective bargaining agreement doesn’t expire until 2021. Among the topics to be discussed will be the state of free agency, service time manipulation and the luxury tax.

The MLBPA, player representatives and players themselves have become increasingly frustrated with the current state of free agency, lamenting the stagnant market (particularly for second- and third-tier free agents). While many are quick to point out that in some instances, players have harmed their own markets by aiming too high early in the offseason (e.g. Dallas Keuchel, Craig Kimbrel), one of the greater issues on the player side has been the slow disappearance of the so-called “middle class” of free agency. Players such as Adam Jones (via USA Today’s Bob Nightengale), Matt Wieters (via MLB.com’s Jenifer Langosch) and Brad Brach (via The Athletic’s Patrick Mooney) are among the many who’ve been open about frustrating forays into the open market. Veterans Justin Verlander, Marcus Stroman and numerous others have been active on social media in calling out the glacial pace of free agency.

While commissioner Rob Manfred has staunchly dismissed suggestions that a significant portion of the league is no longer attempting to win, players and Union officials have decried widespread tanking/rebuilding efforts that have created decreasing levels of parity and discouraged teams from venturing into free agency amid record MLB revenues.

It’s an exorbitantly layered conversation and one to which there’s no clear and easy fix, so it’s promising that the two sides have agreed to at least begin even preliminary discussions that could lead to a system which all parties find more palatable. Certainly, there won’t be any resolution on those issues anytime in the near future, but the early efforts to maintain labor peace will assuredly be among the more fascinating storylines to follow in the months and possibly years to come.