Kyle McClellan and Ryan Franklin are approaching 70 innings of relief work on the season.  It has long been a belief of mine that the 70 inning mark is a stress point for major league relievers, more or less.  Of course different pitchers will certainly have different thresholds, but just from observing I’ve noticed a general dropoff in performance in the years following a 70 inning plus workload.   It’s been more of an intuitive thing on my part, so I wanted to look up data to see if it supports the theory.  Specifically I looked at pitchers that logged over 70 innings in relief last year, and compared their performance this year (to date) to their last.  The results are alarming,

First, a couple disclaimers.  I just used pitchers that made every outing in relief last season and exceeded 70 innings.  I did not use pitchers that were primarily relievers but made some spot starts.  I also may have missed relievers that logged more than 70 innings work between multiple teams.  The reason for that is that I just went team by team in B-Ref to filter it out for simplicities sake.  If I am missing someone that split time with 2 teams, but still went over 70 innings we can include them in the sample and adjust the totals.  And finally, I have just went through 2007 results and compared to 2008.  One year’s data is far from conclusive, so I’d like to do some other years too eventually.  I may be a little strapped for time in the next few days though, so it may be a while.   

Anyway I found 37 pitchers that logged over 70 innings of (solely) relief work in 2007.  I hesitate to name them all, but I think some might like to know so I will list them anyway.  If you don’t care you can move on to the next paragraph….

***Tony Pena, Brandon Lyon, Pete Moylan, Oscar Villarreal, Rafael Soriano, Bob Howry, Michael Wuertz, Dave Weathers, Rafael Betancourt, Manny Corpas, Jason Grilli, Kevin Gregg, Lee Gardner, Chad Qualls, Dave Borkowski, Joel Peralta, Chris Bootcheck, Scot Shields, Jonathan Broxton, Rudy Seanez, Joe Nathan, Pat Neshek, Aaron Heilman, Mariano Rivera, Luis Vizcaino, Matt Capps, Heath Bell, Cla Meredith, Doug Brocail, JJ Putz, Ryan Franklin, Gary Glover, Joaquin Benoit, Casey Janssen, Saul Rivera, Jon Rauch, Chad Cordero***

Now Janssen has not pitched this year, so there is no point of comparison with him.  The 36 others have pitched, at least a little.  Several have had arm problems this year and have pitched a very limited amount, which may not be all that surprising. 

Here is how these pitchers collectively performed in 2007…

2,921.33 innings, 3.18 ERA, 7.87 hits/9, 2.83 walks/9, 1.19 WHIP, 0.73 HR/9

And in 2008 (to date)….

1697 innings, 4.01 ERA, 8.94 hits/9, 3.30 walks/9, 1.36 WHIP, 1.02 HR/9

Put another way, what we are seeing here is a 26% increase in runs allowed, a 14% increase in hits allowed, a 17% increase in walks allowed, and a 40% increase in homers allowed. 

It is just a one year sample, but I find this pretty damning.  My next question was whether a few bad apples were spoiling things for the whole bunch.  Well, not really.  Of the 36 pitchers with data for both years, 25 of them (69%) were worse in ERA, 27 (75%) worse in hits allowed, 20 (56%) in walks, 30 (83%) in WHIP, and 24 (67%) in HR’s allowed.

So here we are.  All hopes of making the playoffs are lost.  McClellan is approaching 70 innings.  He is expected to be a big part of the bullpen next year.  He has shown signs of tiring, and has had major arm surgery.  We have some AAA arms that need to be evaluated.  Can anybody tell me why we would want to push  McClellan to 75 – 80 innings this season? 

I’d just assume they thank him for fighting the good fight, and tell him they have seen enough and get ready for next season.  I think everything points in that direction.  It might not be a bad idea to have the same conversation with Franklin too, for many of the same reasons.