Every September 1, teams across the league call up a myriad of players: some top prospects, some fringe specialists, and the occasional organizational soldier. They all have different purposes leading to one main goal: improving the big league team over the season’s final five weeks. This year looked to be no different approaching September, then began a wave of arguments against the practices of September roster expansion. Historians will identify Joel Sherman of the New York Post as the first writer to shoot. Sherman’s article offered strong language, supporting quotes from those within the industry, and, in a clear act of aggression, a Three Stooges reference. Sherman concludes like so:

By logic, if you are going to have a month with expanded rosters, it should be April when starters are not fully stretched out and players’ bodies are not yet trained to play nine innings day after day. Now, I would not allow any roster expansion: You play 25 in April and May, you should play 25 in September. If you want to see a prospect, call him up and demote or release someone else. If you are worried with the minor league season over about having someone ready should there be a September injury, then expand your Instructional League concepts to keep veteran minor leaguers prepared.

But even if you going to expand rosters and bastardize the strategy of the game, at least come up with a mechanism where each team has to play with 28 or 30 or 32. Or have a taxi squad of up to 40, but you have to declare 25 a day. The idea that playoff spots have been and will continue to be determined by Team A having more players than Team B is something so obviously unfair and unintelligent that tradition, laziness, and partisanship can carry the day no longer.

Baseball clings to its tradition like no other major professional sport, leading to a much-maligned and despised reluctance toward change on hot-button issues. Naturally, the league is working quickly to appease those opposing the current rules. On Tuesday night, Scott Miller of CBS Sports reported that the league is considering instituting new rules for the period of roster expansion. The proposal, as told by Miller, would cap active roster limits at 30 players as opposed to the 40 currently in play. A team’s 25-man roster would lock into place on August 31, as their playoff rosters do, and teams would then have five flex spots to use as they pleased.

Tightening the roster cap is a reasonable solution—a fix bearing resemblance to plans offered in the past by Sherman and Brewers general manager Doug Melvin. Nothing really changed in the process, except those worried about a busybody manager ruining the integrity of the game can now focus their attention on more problematic scenarios—such as players not taking the All-Star Game seriously. Whatever validity there is to those fears seems to stem from isolated incidents and cynical what-if analysis. As a whole, teams appear to operate as though they were reasonable human beings:

Substitutions Per Game, 1993-2010


Subs  Per Game
















Teams do use more substitutions late in the season, but that is to be expected. The key number is two-to-three—or the difference in substitutions per game between the pre- and post-expansion games. We could see the gap remain steady even under the new rules, thus eliminating the illusion of added competitive balance and outing these changes as a way to prevent a doomsday scenario.

One positive of the proposed changes is an added tactical element previously unseen. By allowing teams to cycle players on and off the active roster, the league is forcing teams to strategize based on opponent and a slew of other factors. Teams will have to pick between a second or third left-hander in the bullpen or a pinch runner on a daily basis; it’s as if the league were baiting Tony LaRussa into returning.

Amongst the logistical issues worth discussing: how the pay and service time will work for the inactive players. One would assume the players would earn a raise and big-league service time once recalled, independent of whether they appear in games or not. Any other arrangement is likely to earn the ire of the Players Union. More critical to fans are the limitations placed on the August 31 roster. Can a team replace a player from the August 31 25-man roster if the player is later injured or traded? And what about players on the disabled list at the time of roster expansion? You wonder if the league might adopt a policy as exploitable as the one governing playoff rosters. Then there is the Stephen Strasburg shutdown, as pointed to by Miller.

Having more questions than answers at this point is common. In an era where every statement, trade, or alteration can result in an overreaction, consider it a win for both baseball and common sense that no one is taking offense to the changes.

Special thanks to Colin Wyers and Jason Collette for research assistance.

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The most egregious abuse I can recall in this area is when then general manager Jim Bowden was denied the funding to significantly expand the September roster of the surprisingly contending 2005 Washington Nationals under MLB ownership. No permanent rule change can be expected to account for the possibility of that kind of outlier in such a way as to prevent a similar abuse should another team fall into MLB's lap, as is bound to happen some time in future (absent the complete collapse of baseball in an economic cataclysm).

I see future Septembers bringing diminished opportunities for MLB fans to see that season's hot prospects in person, while retaining numerous (NOT 'myriad', if you please) possibilities for postseason-roster jugglery and lawyering. Verdict: FAIL.
it seems to me that this article completely ignores the fact that minor league regular seasons are finished so unless the team makes the playoffs why not allow those players on the 40 man to get a taste of the big leagues?
Ironically, the fact that your "fact" is untrue -- some but not all farm teams will continue to play for some time, in their own post seasons -- is really about the only justification I consider valid for changing the rules. Teams whose farm systems are deeply involved in playoffs are handicapped in bringing guys up, unless they don't mind enraging the farm systems. That leaves them at a disadvantage compared to teams whose farm teams really are done for the year. (Has this been studied? Is there a [negative] correlation between number of guys called up and playoff appearances by the AAA and AA farm teams? It seems like there would be, but objective data should exist.)

Otherwise, I don't understand the pressure for this change. What problem needs solving here? Seeing farm hands showcase themselves in September isn't a problem, it's an opportunity, and the opportunity is available to all teams. Failure to take advantage of it rests on the team, not on the concept of expanded rosters.
Amendment: I see that you didn't ignore the farm-team playoff exception at all, excuse me for implying that you did. However, I do think it's important as a constraint on who gets called, and that does produce an inequality.