Should We Worry About Jordan Zimmermann?

Jordan Zimmermann has been my favourite National* since I started following the team closely in 2009. (Despite the pitiable record, still one of my favourite seasons, as Mike Rizzo coped with a roster he did not assemble.) I have found his starts this season, however, somewhat lacking in the standards previously established by him. I thought about looking into it, and I have assembled a few charts from BrooksBaseball.com to illustrate my concern.

First, here is his start on 18 May, against the Mets:

Then, a start from exactly one year ago, 18 May 2013, against the Padres:

And, finally, a start at about the same time of year against the Mets, 4 June 2013:

The first thing to note is that Zimmermann is throwing a lot more change-ups, and a lot fewer breaking balls. Theoretically, this is good, because breaking balls apparently lead to arm trouble. However, his fast ball does not appear to be moving as well as it did in his starts last year. In fact, even his change-up isn't moving quite as well as it did last season. His PitchF/X velocities as recorded at Fangraphs.com show his average fast ball travelling at a slower speed, while his breaking balls are a bit faster. Going back to the charts note that the fast ball spread is not as tight this year as it was last. The slower ones are a bit slower, and there aren't quite as many faster ones. Now, the charts also show his numbers so far for 2014 are comparable to the 2012 ones rather than the 2013 ones, and that overall he has gained velocity since 2009. It's all a bit of a muddle, and I have no conclusion to offer, only that question. Should we worry? Let's create a watching brief on this one.

EDIT: I stupidly forgot to mention that Dave Jageler's comment about Zimmermann being 'wild in the strike zone' during the radio brodcast on 18 May against the Mets was what sent me to look at BrooksBaseball.com In fact, it seems more true of 2013 games than the one on 18 May.

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*Jayson Werth is my favourite positional player, but I like pitchers best of all.

A Note on Radio Guys

Back in 2010, when the San Diego Padres were in the race for the National League West title, I found myself often tuning in to their broadcasts. One of the things I do for Nationals (and other teams I might follow closely) is keep score. But when I do a 'bedtime broadcast', picking up a West Coast game not involving a team I am tracking, is just listen. It isn't quite an aural wallpaper, because I'm listening to hear opinions of other players, but I don't pay as close attention as I would to the mighty duo of Charlie Slowes and Dave Jageler.

Well, except I also have a habit of listening to the visiting broadcasts on GameDay Audio. I do this to get insight into the park.

Back in 2010, I was entertained by Leitner's voice, but this time I found his commentary made it very difficult to track the game statistically. (He also offered some bone-headed views on sabermetrics.) I post a negative note because this is the first time a visiting broadcaster has driven me away from their coverage in quite a while. I'm not sure if I've changed or if Leitner has.