14 May 2008

Daniel Cabrera's Batted Balls

Daniel Cabrera pitches tonight against the typically patient and talented Red Sox offense. He has been able to string together six seemingly good games in a row. Several of his game scores were not impressive during this period as three were in the 50s. This helps give the impression that he has changed and is a much better pitcher. In fact, quotes are beginning to be dug up by unnamed scouts declaring the Cabrera has turned the corner and is now a legitimately fulfilled talent. Now, he might be. He might actually be a very good pitcher now. He certainly is throwing differently as in he has really imploded in any start this year other than his first. He has certainly comes close several times during this stretch though. I mentioned in a previous post how his peripheral numbers do not make any sense and that he is more truly a 3 or 4 and not an ace as his current ERA suggests. Today we are going to look more into his batted ball data.

Battered Balls
I have taken his batted ball data from baseball reference and normalized it to the 2007 AL batted ball data. As you may realize, changes in batted ball data can be explained by: 1) changed pitch run (this is quite rare for an established pitcher to drastically change how his pitches run to the point that his batted ball data would also change dramatically), 2) improved defense (this can greatly improve or hinder BABIP, but typically teams do not make wholesale changes in defense from year to year), and 3) pure luck (batted balls are typically not uniform in their dispersion over the course of partial seasons and sometimes full seasons). Using that base knowledge, we are able to discern potential discrepancies in Cabrera's batted ball data.

Infield and Outfield - BABIP of balls hit to these respective areas
BABIP - Overall batting average of balls in play
First, Middle, and Third - BABIP of balls hit to these areas of the field, including the outfield
GB, FB, LD - BABIP of balls classified as groundballs, fly balls, and line drives.

When you look at a graph like this, you look for extreme differences. A difference of about 20% is a good rule of thumb for identifying extremes. Using that as a benchmark we have these weird BABIPs: overall BABIP, infield, third, middle, groundballs, and line drives. It is good to categorize the data because it can give us better ways to identify what is going on here. BABIP alone shows that something weird is going on, but the rest of the data suggests why.

Fielding cannot really be relied on as having changed. Much of the difference looks like it applies to groundballs going up the middle and to the right as well as line drives in the same area. The only difference in the infield is Luis Hernandez and he got benched because of poor defense. There are seems to be little reason to think that Brian Roberts or Melvin Mora have been significantly better at what they do this year. In the outfield, we have Adam Jones and Luke Scott. I think we can say Luke Scott improved our defense. I also think Adam Jones is better than Corey Patterson. I also think the differences between this year and last is just not enough to explain the differences. What is telling is that difference in line drive percentage. You can explain away grounders by suggesting Cabrera is inducing weak groundballs, which is plausible (though I doubt with his repertoire of four seamers--it should be noted that althought I see little difference between pitch quality this year and last beyond placement . . . I could certainly be wrong about the quality of his stuff compared to last year). You really can't explain his dramatic difference in line drives. Line drive success has little to do with good defense and more to do with simple luck. Not only is his line drive percentage unsustainably depressed . . . the line drives that are actually hit off him are going straight to his defenders at an unsustainable rate. Add this to my doubts about the groundballs being more effectively covered and you have a guy who is ripe for a downturn in success.

I will be bold and predict that Cabrera has trouble tonight. Some people will point to his 116 pitches in his last outing. Others will just say he is no good. Or maybe he will balance a dozen plates and toss 8 innings and give up a run or two. My guess though is that he will eventually drop down to about an era in the high 4s by the end of the season. He has been lucky avoiding baserunners and getting out of jams. His LOB% is about 10% above where it should be. His K/BB is 1 when people are on base, which is a third worse than league average. There just isn't much to like with him going up against a team with the 3rd most walks, best obp, and the best slg in the AL. Anyway, cross your fingers

1 comment:

Jon Shepherd said...

5 innings into today's game . . . and it seems Cabrera is still doing it. Maybe my Kung Fu is no good.