What To Expect From Jeremy Bonderman (Graphs Galore)

There's been talk of Jeremy Bonderman possibly getting into the Detroit Tigers bullpen when he's ready to return to Major League action. First question is: Can he be effective? Second question is: what should we expect?

Well, to answer the first question, I figure we must look at some PITCHf/x data.

First, let's look at the average pitch flight for Bondo's pitches in 2008 (click all images to enlarge):


It gets a bit fuzzy to see, but his 2-seamer (FT; orange line) had absurd amounts of arm-side run -- also called "tailing action." His 4-seamer (FF; blue line) had less and both had okay downward movement -- he's not a big time ground ball pitcher, so we wouldn't expect great downward movment.

His slider (SL; red line) comes with sweeping action, but not a lot. The amount of drop he gets on it is what made it such a good swing-and-miss pitch. The first base view shows it leaving on the same layer as his fastballs, but it finishes at home plate at the closest to the ground. Just great diving action it as it falls off the table, if you will. His change-up (CH; white line) had some okay arm-side run and decent sink. It's what fans and the Tigers alike felt was his worst pitch, and I think I'd tend to agree with that.

Now, he's made one appearance in 2009 -- a start in a double-header against the White Sox in Chicago. Firstly, here's his strikezone plot:

Here's the pitch flights from that lone outing:

I can see some differences, but to make it an easier graph to read, I'm going to compare each of his pitches to their counterparts. Up first, a comparison of his 4-seam fastball from 2008 and 2009:

Here, we see that his 2008 4-seamer has more arm-side run on it, and a bit more sink. So, his 2009 version has less movement overall -- both tailing and diving action.

The difference on the 2-seam fastball is much more pronounced. He didn't throw many in his 2009 start, however, you can clearly see his 2008 2-seam fastball had a ton of arm-side run and okay sink, while his 2009 version is much less in both.

His 2009 change-up seems to have some more tailing action, but not much. The sinking action goes to his 2008 change-piece. So, it's gotten a little more flat, but it's still his worst pitch to throw.

The slider, also, seems to have lost a tick of sweep and some downward movement.

Conclusion

So, to answer the questions from before:

1) Can he be effective?
A: I don't know. My gut feeling is that his stuff doesn't look to be markedly better than the relievers we have in the bullpen at the moment. Then again, relievers are unpredictable and maybe there is lightning in a bottle to be had. An extra arm is never a bad thing, so long as they aren't over used if they're ineffective.

2) What should we expect?
A) Honestly, not much. The usual caveats apply: his 2009 sample is pretty small, but if they give any of the slightest indication, his stuff's obviously declined (and you don't need PITCHf/x data to tell you that). Unfortunately for Bonderman, the Tigers, and myself (been a staunch supporter and driver of the Jeremy Bonderman Will Turn The Corner This Year bandwagon), I don't think his stuff will make him a top-notch reliever in short bursts. I'm not so sure it even makes him better than a Brandon Lyon at this point.