A simple fact of the baseball postseason is you don’t get in without a strong bullpen, and you certainly don't survive without one.
These teams believe in their pens, and they tend to especially have supreme confidence in their closer. Almost invariably you look at the numbers and see that when these teams have the lead in the ninth inning, the game is over. And that kind of confidence must carry into the postseason.
Since postseason contenders typically feature a dominating closer and an effective setup man in their bullpens, the guys who really make a difference are the next three relievers in line. They are the one-out specialists, the guys with funky arm angles, wipeout breaking balls and rubber arms who can pitch without rest. Bullpens that can offer a multitude of looks and dictate matchups are the ones that succeed in October.
If we look at a team’s overall bullpen statistics, we do get a pretty good feel as to how they performed as a whole during the regular season, which to an extent is an indicator of how they should do in the postseason. They are the best bullpens, and the numbers back up that fact (see chart below).
Below is my ranking of the top seven bullpens among postseason contenders. Not only did I take into account the statistics and scouting reports, but after all my years in baseball as a general manager, I know I also have to factor in mental toughness and an intangible “gut feel.” This ranking also is mainly based on the top four or five relievers of a bullpen, since they will likely get the bulk of the action. If the last two men out of the pen in the postseason are integral to a team’s performance, that team isn’t going very far.