Relief pitchers are increasingly like NFL running backs -- their performances can have high impact, sometimes for a relatively short window of time, and they are mostly compensated as if they are disposable. Teams will search for just the right bullpen piece, and when they find him, he'll get the ball time and again until he breaks or struggles ... and then the team moves on to find another reliever.
The volatility of bullpens is legendary. The Cleveland Indians rode relievers Cody Allen, Andrew Miller and Bryan Shaw to within one win of a World Series title in 2016, and in less than two years, Shaw was struggling for the Rockies after departing as a free agent, Allen was fighting to keep his closer job with the Indians and Miller was working through injuries.
At the outset of the 2018 postseason, the Red Sox relief corps was the team's greatest uncertainty -- and by the end of October, these pitchers were postseason heroes getting sized up for championship rings.
You'll forgive Red Sox manager Alex Cora, then, if he won't overreact to the events of the winter.