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One More Crack at Dissecting Bullpen Usage

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Last week I took a look at how the Rays' 2009 high leverage FIP of 4.87 underperformed their season FIP of 4.36 while the average team fares 0.25 better (lower) in high leverage situations. I proposed that this was due to inefficient bullpen management. According to The Book by Tom Tango, pitchers should perform to the same ability regardless of situational leverage. Therefore, teams should use their best pitchers when the moment is the most critical.


Low Lev Med Lev HI lev
TBR  4.61 4.1 4.87
AL AVG 4.51 4.52 4.25


If we are to further isolate High Leverage opportunities by the bullpen only we see this:


Bullpen 0.713 4.32
BP Hi Leverage 0.791 5.18


The Rays have basically had a Big 3 in the bullpen this season comprised of J.P. Howell, Dan Wheeler, and Grant Balfour. Based on Tango's study referenced above, these 3 should be receiving the lion's share of high leverage work.  Here are their high leverage numbers compared to the bullpen:

BP Hi Leverage 0.791 5.18
Big 3 Hi leverage 0.653 4.07


So when the Big 3 have been called upon they have performed by about 0.25 better according to FIP than the bullpen. Yet, the bullpen overall has been a massive failure in high leverage situations. Is that because there were more high leverage innings than innings of availability for the big 3?


Consider this: 26.3% of batters faced by the bullpen were of the high leverage variety. The Big 3 have accounted for 42% of total bullpen usage. 60.3% of high leverage opportunities have gone to the big 3 which means Big 3 high leverage opportunities account for 16% of the overall bullpen use. So the big 3 account for 42% of total usage of which 16% is high leverage. This leave 2/5's of the high leverage spots to the rest of the cast.  This does not seem to be the most efficient use of  resources as the Big 3 should be able to sacrifice low and medium leverage opportunities for higher spots.


Another point Tommy Rancel has been all over is Joe Maddon's tendency to over extend a starter into a new inning, only to remove them upon the first runner reaching base. The bullpen's OPS against for 2009 is .713. With runners on base, it rises to .824. Similarly, the starting rotation's performance decreases drastically as the lineup flips over for the fourth time.


Bullpen 0.713 4.32
BP w Runners On 0.824 4.37



1PA 0.250 0.319 0.409
2PA 0.261 0.330 0.415
3PA 0.264 0.325 0.435
4+PA 0.339 0.377 0.600


When a starting pitcher is near 100 pitches as the lineup flips for the fourth time around, the Rays would be well advised to turn it over to their bullpen with the bases empty. The fresh arm should experience greater success without the added pressure of inherited runners.

The last issue to discuss involves frequent pitcher changes once into the bullpen. The average Batters Faced per Relief Appearance in the American League since 2006 is 4.82. In 2009, the Rays are averaging 3.92. The second lowest figure over that period belongs to the 2007 Boston Red Sox at 4.15.  Last season with largely the same bullpen the Rays were at 4.55.

The 2009 Rays bullpen is on pace for 507 total appearances or 3.13/gm which since 2006 is second only to the Yankees at 522. Lets take a look at the top 5 bullpens in terms of total appearances since 2006 and compare their Season FIP to that of August. Please note I pro-rated 2009:


Year Team Appearances BF/App FIPs FIPa difference 
2007 NYY  522 4.49 4.64 4.69 -0.05
2009 TBR  507 3.92 4.36 5.2 -0.84
2008 BAL  492 4.97 4.74 5.13 -0.39
2007 BAL  490 4.92 4.85 5.37 -0.52
2006 NYY  489 4.63 4.47 4.8 -0.33
Avg -0.43
Avg of All teams 0.04


So the top 5 most worked teams in terms of relief appearances since 2006 all suffered performance drop offs in August while the average change among all teams was a nominal improvement.


Now let's look at the five most taxed bullpens in terms of batters faced:


Year Team Batters Faced BF/App FIPs FIPa


2006 KCR  2581 5.46 4.97 5.26 -0.29
2008 TEX  2564 5.6 4.55 4.2 0.35
2007 TEX  2556 5.47 4.24 3.66 0.58
2008 BAL  2443 4.97 4.74 5.13 -0.39
2009 BAL  2,424 5.25 4.42 4.25 0.17

This is much more in line with the average among all teams of .04. It seems that fewer bullpen appearances that go longer are less fatiguing over a season than more frequent shorter appearances. Perhaps the Rays have not accounted enough for the effort burned during warming up in the pen.

In summary, I am of the opinion that the Rays season was affected by misuse of the bullpen. The best relievers were not used frequently enough in high leverage situations. Starters were left in too long, often the dreaded fourth time around the order, forcing the pen to habitually come in with runners on base, a scenario in which they proved to be less effective. Finally, the entire bullpen broke down during the homestretch due to excessive turnover  causing  too many bullpen appearances.