The MLB closer has one of the toughest jobs in baseball and inconsistency at that position is one of the most frustrating things a fan of the game can experience.

It is very difficult for a team to find a closer that can be relied upon to be successful in that role year in and year out. Mariano Rivera of the Yankees is one of the rare examples of a closer that remains consistent from year to year.

A great example of the inconsistency of closers is the Detroit Tigers Jose Valverde. After being perfect in save opportunities a season ago, Valverde has already blown three saves this year.

Here is a look at the five most frustratingly inconsistent closers in the MLB this season.

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