Baseball traces its origins back over two hundred years. The sport has evolved constantly since that time. Today’s game would be incomprehensible to the guys in a field in the early Nineteenth Century. Much like the English Common Law, changes in the rules have occurred to accommodate fair competition, or to gain a tactical advantage, without disturbing the balance of the game. One example is the Infield Fly Rule, which prevents a team from achieving a cheap double play by allowing a pop fly to drop and forcing runners.
The most dramatic change in my time has been the advent of the Designated Hitter, at least in the American League; but also widely in the minor leagues and college and high school and even Little League. When I played “beer league” softball, we had ten fielders, plus a DH and an “extra hitter”, for a batting order of twelve, two of whom did not play the field.
Other changes have been more subtle, occurring only over multiple years (at least, until the inexplicable surge in home runs in 2019). For example, starting pitchers now rarely throw a complete game, something that was still common in the 1960’s and fully expected before that. This led first to the advent of “closers” and then to the importance of “middle relief” and bullpens. For the first half of the Twentieth Century, the guys in the bullpen were failed – or injured – starters. There were few if any relief specialists. By the turn of the Century, teams were concentrating on closers and the bullpen almost as much as on reliable starters.
Perhaps we should have seen this coming. Having effectively truncated the responsibility of starting pitchers at the end of the game, in the past couple of years managers have begun to eliminate the role of a starter from the first pitch. Teams with strong deep bullpens have occasionally forsaken a starting pitcher entirely, instead using a reliever as an “opener” for an inning or two, to be followed by a series of middle relievers, and, if successful, the closer. The trends is not yet widespread, but it is surprisingly being utilized in the post-season, the most important games of the year. That suggests that it will grow in the future.
One perceived advantage of using an “opener” is rest for the starting staff. With the prevalence of five-man staffs, the need for further rest seems surprising. Rarely does any starter exceed two hundred innings any more, something that was common in the days of four-man pitching staffs and complete games. Sometimes a starter may be injured, and an opener is preferable to moving up the entire rotation to pitch on less rest, or hustling up an unproven minor leaguer for a spot start. Of course, the usual practice in past years would have been to throw one of the failed starters in the bullpen; but today those guys are all specialists.
The advent of the opener approach can also be attributed to sabremetrics. Managers now have access to statistics that show how many starters lose effectiveness after their first time through the opposing batting order. The second and third time through, “familiarity breeds success” for the hitters. Somehow, seeing a pitcher for the second time around creates more of an advantage than the pitcher feels in facing the hitter again. Someday this approach will yield a perfect game, where each of three hurlers faces nine hitters.
The downside of using an opener and a “bullpen game” is that all those pitchers will be tired, and some will not be available the next day. If the following day’s starter does not pitch deep into the game, the manager is left with a bunch of guys who have pitched the day before, and who may not be effective on a second straight day. The opener approach can easily snowball, to the point that the bullpen is being overused. The need for fresh troops has contributed to the expansion of bullpens to seven, eight, and even nine pitchers, with either one less starter, or fewer bench players. The latter is particularly true in the American League, where the DH Rule means fewer pinch hitters are needed.
Like so many other changes in baseball, the use of openers will spread, if the experiment is deemed to be successful. If so, I can even foresee a team that abandons starting pitchers entirely, in favor of ten or eleven or twelve hurlers who can pitch a few innings each, every other day or so. This novel approach would be a logical extension of how young pitchers are groomed for success. With the widespread use of pitch counts, for fear of arm injuries, few if any young pitchers throw 100 pitches in a game. Rather, the widespread gospel is to throw “as hard as you can as long as you can”, and then give way. (Note that this approach has arguably increased, not decreased, the incidence of severe injuries to pitchers.). It’s a system geared to produce hurlers who can last three of four innings, or one turn through the lineup.