We recently took a look at the Tigers team defense through the eyes of David Pinto’s Probabilistic Model of Range. As Pinto wraps up this season’s numbers, he calculated the PMR behind each pitcher. Not much went right for Nate Robertson this year, and it is little surprise that his woes were reflected in the PMR numbers as well.
The table below is a combination of Pinto’s PMR work and batted ball data from Fangraphs.
Nate Robertson had the 7th lowest rate of balls in play converted to outs in Major League baseball. Now Robertson wasn’t particularly unlucky – at least in regard to his fielders letting him down. His defense only made 2 fewer plays than expected behind Robertson. Robertson also posted one of the lowest expected DER’s in baseball as well.
What is unexpected is why that rate is so low. Looking at his batted ball stats, they aren’t remarkable in any way. His line drive rate isn’t high, his infield fly rate isn’t low. His ground ball and fly ball rates are consistent. Yet his expected DER is a recipe for disaster. Is it that Robertson was especially unlucky in that a disproportionate number of balls were hit to locations where nobody could get to them (save the “over-the-fence” jokes, those aren’t in these stats).
Meanwhile, Armando Galarraga was on the opposite end of the spectrum. He had a high expected DER, plus his defense helped him out to the tune of 16 plays. Kenny Rogers gave up a fairly high line drive rate, so his struggles aren’t at all surprising. Justin Verlander was hurt by his defense to the tune of 4 plays, but hardly was that the main source of his struggles.
But back to Robertson, I don’t know what to make of the data. Sometimes it feels like a cop-out to chalk things up to luck, and I saw Robertson struggle – especially in the second half. His peripherals did slip with Nate fanning a few less hitters and walking a few more, but those shifts paled in comparison to the .343 batting average on balls in play. If he was giving up line drives all over the park, it would be easier for me to chalk things up to a lack of stuff. That wasn’t the case. It truly does seem like the opposition managed to “hit-em-where-they-weren’t” with remarkable consistency last year.
It would be interesting (but not interesting enough for me to do it) to see if good pitchers tend to have good DERs, and poor pitchers poor DERs. Untested theory:
Assume that defensive positioning is related to what a pitcher throws and what location he’s aiming for. A reasonable assumption, I think.
With that assumption in mind: a good pitcher is more likely to hit his spots. A batter is, thus, more likely to hit the ball where a fielder is positioned. Whereas a poor pitcher is more likely to miss his spots, and the ball might go anywhere. In short: against a bad pitcher, a hitter is more likely to “hit ’em where they ain’t,” even if you leave “over the fence” out of the equation.
I have no proof, it’s just a thought.
Billfer my thought to Nate’s struggles
Maybe it’s a combo of “hit ’em where they ain’t” and very hard hit liners/grounders/fast moving flies on average
Since besides Inge I don’t think we have any great instincts fielder that might be the case.
Just think about it – usually the only reason a fielder can’t field a ball is he can’t get to where the ball is hit fast enough, or it is hit too fast for him to get there in time – which are kind of one in the same…
Hmmm…. I don’t know how to explain what I’m trying to say(in response) in an awesome way but I’ll try anyway
Lets just say he was hit hard…hit too hard…and too often…for most of the time… not allowing fielders to react in a manner conducive to obtaining an out relative to other Major League pitchers
Maybe that will suffice? maybe not…
Still I hope he’s pulls a Cliff Lee and is doing pull ups between trees in the woods right now 😉
Nate Rob actually had solid peripherals for the first 3rd of the season or thereabouts. Then the wheels fell off. Couple that with bad luck and you have a LHP with high 80’s FB, loss of control, and a demotion to the bullpen on a team that was a disappointment. He kind of sums up the Tigers season in a nutshell.