The most contentious decision for a fantasy baseball owner is always which closers to draft. Closers, unlike arguably any other position, come with the greatest degree of risk.
The best example of this is perhaps New York Yankees great, Mariano Rivera. Prior to 2012, Rivera owned a sterling career 2.21 ERA, 0.99 WHIP, 4.04 K/BB and 603 Saves. The future Hall of Famer also hadn't ever missed significant time due to injury. But this all changed on May 3, 2012. Prior to a game against the Kansas City Royals, Rivera awkwardly fell and tore his anterior cruciate ligament (ACL) while shagging fly balls in the outfield. The season-ending -- and, at the time, potentially career-ending -- injury was a freak occurrence, yet it exposed how truly unpredictable, and unequivocally infuriating, closers can be.
People who drafted Rivera were likely trying to avoid the agita involved with owning the likes of Carlos Marmol, Huston Street or Javy Guerra -- closers who likely would have hurt a fantasy team's ERA, gotten injured or lost their job to a superior pitcher, respectively.
Yet, as much as an anomaly as Rivera's injury was, closers' knack for losing their jobs due to injury, ineffectiveness or trade (usually a team "selling high") is well documented. Looking at the past three seasons confirms this.