Debunking the Doomed Bullpen

The performance of the 2009 Ray's bullpen has remained at the top of the most frequently discussed team talking points all season. Why not? After having a tremendous run in the 2008 season, it seems like there are multiple heartbreaks each week   Outside of the previously discussed regression, how much validity is there to the criticism?

For the sake of comparison, we will look at the bullpen performance in 2007 (worst ERA and FIP in the American League), 2008 (3^rd best ERA and 7^th in FIP) and 2009 (7^th in ERA and 9^th in FIP). The 2007 bullpen was widely considered to be a joke while in 2008 they were deemed a force.

The first variable to consider is team defense. In 2007, The Ray produced a UZR/150 (Ultimate Zone Rating over 150 games) of -6.5, bad enough to qualify as second worst in the AL. In 2008, Andrew Friedman had constructed the top ranked defense in the AL with a UZR of 11 (Gabe Gross who?). This season the Rays continue to have the top performing defense. What was the net effect on the bullpen?

It would make sense that the 2007 team would have the highest BABIP (Batting Average on Ball in Play) given the porous defense evidenced by the UZR/150. That also jives with the ERA exceeding FIP by almost a full point.

In 2008, the team defense was much improved giving the Rays an expected BABIP of .290. The Rays were fortunate enough to outperform that at .267. However a reduction from 2007 levels would have been expected based on the defensive improvement.. The outperformance led to a lower ERA than FIP.

In 2009, the teams FIP is once again higher than their ERA which should be the case on a team with a much greater than average defense. However, BABIP has regressed to the expected level. The bad news is that the team FIP has jumped by .46. Let's see why.

The strikeout rate is at a 3 year low and almost 1.5 K/9 off of last years rate. It feels surprising to the naked eye to see walks down, but that's why it's helpful to step back and look at season numbers after a one game implosion before launching into a tirade. Home runs are slightly up but still at a manageable rate. Given the expected increase in BABIP and the decrease in strikeout rate, the Rays seem fortunate to still be in the ballpark of last season's strand rate. Now let's look at the batted ball data to see how that may affect this information:

In 2009 the bullpen has surrendered a significantly higher number of pop-ups while also increasing the number of ground balls induced. These numbers have helped offset the decline in strikeouts leading to only a slightly reduced strand rate.

Plate Discipline has remained extremely consistent:

 Teams are making more contact out of the zone, most likely due to the decrease in velocity. Outside of the effect of this reducing strike out rates, there is not much here indicative of a change in year over year performance. Velocity is not necessarily an indicator of strikeout success as the soft-throwing J.P. Howell leads the team in strikeout rate (prior to David Price). However on average, reduced velocity will lead to more contact.

What about the concern of overuse of the bullpen? Scott Kazmir, Jeff Niemann and to a lesser extent Andy Sonnanstine have struggled to pitch deep into games. What type of pace is the bullpen on in terms of the number of pitches?

The bullpen is on pace for about 4.8% more pitches thrown than last year but still less than 2007. The problem has been that extended use has come in spurts, possibly impacting short-term performance cycles.

To summarize the bullpen's FIP has increased mostly due to lower strike out rates, but they have induced a greater % of ground balls and pop-ups. The BABIP has regressed to be in-line with the expected vale of the Ray's caliber of defense. Strand rates have remained fairly stable. Why are we so much more frustrated this year?

The answer is found in the team's performance in high leverage situations.

In 2008, the Rays produced a WPA of 9.3. When you remove the leverage index from the equation their WPA was reduced to 4.65. This year the pattern of #'s is reversed. With leverage, the Rays have posted a WPA of -1.4. If you remove the leverage, their WPA/LI is a positive .19. While not spectacular, it evidences what situations are resulting in failed outcomes.

What is the solution for the increase in high leverage failures? The Rays have had just about every reliever fail multiple times this year so it's hard to pinpoint it on one guy. Based on the consistency in other categories, I'm willing to put it on bad luck for the first quarter season with a sense of optimism for improved results to come. Hopefully, going forward, occurrences of failure will happen when it matters less.

This data is also over weighted by the fact Lance Cormier has accounted for 34 of 145 (23.5%) bullpen innings pitched, has had the best results (though lowest K rate), and has pitched in the lowest leveraged situations

All stats courtesy of fangraphs.com