If there is one thing this postseason has taught us, it's that closers are made, not born. The closers for all four championship series clubs -- Koji Uehara, Joaquin Benoit, Kenley Jansen and Trevor Rosenthal -- did not begin the season in that role, yet they have been among the most dominant closers in the game this year.
The clubs that are no longer playing are already planning their offseason moves, and for some teams, that could mean acquiring a closer. However, some teams have an internal solution ready to step in, so let's take a look at the guys who could be the talk of the league a year from now.
The Yankees face the biggest challenge in that their new closer will have to replace the greatest closer of all time, Mariano Rivera. Fortunately, they likely also have the best closer-in-waiting in the sport, Robertson.
There is some skepticism about his ability to handle the role because of his brief stint filling in for an injured Rivera in 2012, as Robertson finished that year with more blown saves (3) than saves (2).
Relievers frequently fall victim to judgments based on small sample sizes, as Robertson has. However, Robertson also has a sufficiently large sample to conclude that he is a very good reliever. Over a career of 329 innings, Robertson has compiled a 2.76 ERA and has bettered that mark in each of the past three seasons. Since 2011, Robertson has struck out 12 batters per nine innings, a rate that has him in the top 10 among pitchers with at least 100 innings pitched.