Chicago Cubs: Justin Grimm and obsolescence by design

Heavier workloads for relievers

By comparison, fire-balling starters typically will burn brighter but not as deeply into games. This means for every extra max-thrower added to a rotation, the innings burden grows further on all those failed converted max-throwing relievers. (And if a starter goes down with injury, the burden gets heavier still.)

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Stats bear this out. Last year, major league bullpens averaged a record-setting 549 innings. This is up more than 8% since 2008 and nearly 14% since 2000 (483 innings). With each bullpen inning representing roughly one appearance, that’s a lot of extra work to spread around the ’pen.

Consequently, most teams now have at least five relievers making 60 or more appearances a season. This included the Cubs last year: Carl Edwards, Brian Duensing, Pedro Strop, Hector Rondon and Grimm (including his minor league work).

Wade Davis also fell one game short of 60. However, his workload as closer was inherently not as great for several reasons.

For one, closers (and exclusive 8th inning set-up men) are stronger, more effective and more pitch-efficient pitchers. That’s why they won the closer spot. Two, non-closers must warm-up quicker, on shorter notice and sometimes multiple times before entering. Three, once a closer warms up, he almost always enters the game. Such is not the case with workhorse relievers, and those non-appearances add invisible wear and tear not in the box score.