What the Hell Happened to Rafael Soriano?

Now that the division title belongs to the Nats, and the race for the number one seed in the NL is pretty much locked up, there are still a few reasons to watch the rest of the regular season games (if you are a Nats fan). If I were an unbiased observer, I would find the whole Rafael Soriano situation fascinating. He was having a fantastic first half, and while his ERA was beating his peripherals by a decent margin, his peripherals were still pretty strong. There was reason to expect regression, but not reason to expect a full-on collapse. But Soriano has picked up over two runs on his ERA during this second half and gone from closer to “cross your fingers mop up guy.” While watching another mentally exhausting Soriano “save” on Sunday, I wanted to figure out what exactly had happened to a season that started out so promising.

One thing that is important to remember is that relievers are volatile, and a few bad outings can throw things out of whack. In September, Soriano has given up 7 ER in 7.2 IP. That’s awful, but it’s also only seven innings. You could find quite a few SPs this season who have had a stretch of 7.2 IP giving up 7 runs. Strikeouts haven’t been the problem either, as he is averaging over a K per inning, and a 3:1 K-BB ratio. And despite the recent blow up (by recent I mean the entire second half), Soriano is still sporting a .59 HR/9 ratio for the season, which is much lower than his career of .86 HR/9. His BABIP is the exact same as last year, his strikeouts are up significantly (6.89 in ’13 versus 8.70 this year), and while his walks are up too, the overall K-BB is stronger. Not to mention that he has the second best SwStr% of his career after posting a career low in the same metric last year. So with all these seemingly positive things happening, what’s the deal? Where has this implosion come from if it doesn’t stem from gophers or a high BABIP against?

I think the answer is two-fold: extra-base hits, and a lack of infield fly balls. Below is a chart from 2013 of hit types against Soriano:

Here is 2014:

There are two important takeaways from this chart. One, even though Soriano gave up more dingers in 2013, he has given up significantly more extra-base hits this season. By my count, he gave up 15 extra base hits last year, and 21 this year (including home runs). Six may not sound like a lot, but that’s a 40% increase. When you only throw 60 innings a season, that makes a huge difference.

Two, look at the location of the outs in 2014 compared to 2013. Notice how there are way more silver dots in the infield in 2013. As a pitcher, infield fly balls are the second best thing to strikeouts. They are an out basically 100% of the time and runners can’t advance on an out like they can on a deep fly ball or a grounder. Soriano went from a 16.3% infield fly ball percentage in 2013 to 7.4% this year. A pattern is forming here. For a guy who pitches with runners on base fairly frequently, infield fly balls and strikeouts are a fantastic way to get out of a jam. Even though Soriano has more Ks this year, he also has far fewer IFFB, which almost offset one another. A lower IFFB% despite a higher overall fly ball percentage from 2013 explains a lot of what’s happening here. More balls in the outfield leads to more extra-base hits or even runners advancing/scoring on an out.

I came up with a quick metric I’ll call “Nearly Automatic Out Percentage” to illustrate my point. Soriano has faced 248 total batters this year compared to 277 last year. He has 59 Ks and 6 IFFBs this year (65 total nearly automatic outs) for a NAO% of 23.5%, compared to 51 Ks and 14 IFFBs in 2013 (also 65 nearly automatic outs), a NAO% of 26.2%. These numbers are closer than I would have thought considering how much better Soriano has been with Ks this season. But when you factor in the additional extra-base hits and a few additional walks/HBP, it explains how the end result in 2014 can be so similar to 2013 (nearly the same WAR, ERA, and xFIP in 2013 and 2014) in two completely different ways.