At the beginning of September, Major League rosters expand from 25 to 40. The “September call-ups,” as they’re called, are players from the minors who are either (a) prospects getting their first taste of some Major League experience in a relatively low-leverage situation; or (b) depth guys who give managers extra bullpen arms and pinch runners and stuff. Teams who are not heading to the playoffs tend to use it for the former purposes, teams which are, the latter. Though that has blurred in recent years.
Another thing which has happened in recent years is people getting cranky about the very nature of September callups. They worry that, with some teams using September as a glorified version of spring training and others trotting out a phalanx of bodies, baseball’s competitive landscape is degraded. Last year Zack Greinke complained about it loudly, saying it was unfair. A few years ago a prominent national writer framed it thusly:
It directly impacts the pennant races, alters the integrity of the game, and could mean the difference between a team sitting home or playing in Game 7 of the World Series.
This is one of those things where, sure, I hear and understand the conceptual problem and appreciate that, yes, the landscape does change due to the callups. Heck, I’m usually quicker than a lot of people to note theoretical and conceptual changes and worry about the problems they may create. I’m a big “principle of the thing” guy in most cases. But I question, though, whether the impact of this change is in any way significant enough for us to worry.
Unless I’ve missed something, I’ve never seen a study about how teams which call up more players win or lose more than they may have expected or whether their opponents are given an unfair advantage or disadvantage. With a few exceptions I can’t even remember individual games turning on some 32nd man on the roster. At most, I suspect anyway, it just makes for some longer games because of excessive bullpen use.
I don’t love to watch games with teams with uneven amounts of players playing because it messes with my love of symmetry and fairness and emptying an 11-man bullpen makes for sloppy baseball. To combat that I’d prefer allowing teams to only use 25 guys for any given game yet, in order to accomplish those 40-man roster goals, let them shift who is eligible and who is not on a day-by-day basis with all other roster rules regarding options and stuff relaxed. Seems like a nice compromise.
In the meantime, let’s not get too worked up about the alleged unfairness of 40-man September rosters. It’s more annoyance than problem, I suspect.