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Diagnosing Rafael Soriano’s Woes

To say that Rafael Soriano has struggled so far this season would be akin to saying Babe Ruth was a decent ballplayer: you’d technically be right, but off by multiple factors of ten. Soriano has struggled mightily since making his Yankee debut, allowing at least one baserunner in nine of his ten appearances, and posting an “Ouch!” inducing 7.84 ERA and 5.55 FIP. He has three meltdowns already this season (only had four total in 2010), and he’s blown two Yankee leads: once on April 5th against the Twins and once last night against the White Sox. Last night was particularly painful, as Soriano plunked Carlos Quentin with a slider and then grooved a fastball down the heart of the plate to Paul Konerko. I don’t think I need to tell you where that pitch ended up.

Since it’s so early in the season, it’s easy to write off these struggles as relatively unimportant; odds are, this is just a slump and Soriano will be his normal, dominant self for the rest of the year. Soriano has only thrown 10 innings this year, so it’s way too early to begin putting credence in his ERA, FIP, or xFIP. But while that may be true, I don’t like leaving analyses at this level; I want to know why Soriano is slumping now. Is this simply a matter of bad luck? Has he changed his pitching approach? Is he struggling with any of his pitches?

To the Pitch F/x data we go!

The first thing you’ll notice when you look at Soriano’s Pitch F/x data is that there seems to some confusion over his pitch classifications. If you look at the Pitch Type section on Soriano’s FanGraphs page, it looks like he’s throwing a similar number of cutters this season, but throwing more sliders and fewer four-seam fastballs. This is data from Baseball Info Solutions (BIS). But if you then look Soriano’s Pitch F/x tab at the top of his player page, which uses the Pitch F/x data as released by MLB, it shows him throwing almost exclusively cutters instead of four-seam fastballs. Here’s the breakdown:

Which should you believe? After looking at the data himself, resident Pitch F/x guru Dave Allen believes the BIS data is more accurate in this case. While it would make for a compelling narrative if Soriano arrived in New York, got apprenticed to Mariano Rivera, and began throwing cutters over 50% of the time, it seems the filters for the Pitch F/x classifications are simply mislabeling his pitches. So if anyone out there was thinking of writing a story about Soriano’s newfound love of the cutter, you can scrap it.

Looking solely at the BIS data, it still appears as though Soriano has changed his approach slightly this season. He’s throwing his slider 31% of the time this year, up from 21% last season, and his four-seam fastball use is down to 52% from 63%. He’s using his slider as a knock-out pitch, throwing it around 50% of the time when he gets in a 2-strike count, while last season he would also frequently use his four-seam fastball in these counts. Whatever the reason for this change – different pitching coaches, his own decision, small sample randomness – the results haven’t been good.

Soriano’s slider is rated as his worst pitch by pitch type linear weights (-2.31 wSL/C), and it’s only generating 6% swinging strikes this season (14% last year). He’s also having a tough time controlling his slider, hitting Carlos Quentin with one last night, and he’s frequently missing with it high in the zone and over the plate. Compare these two strikezone plots of his sliders:

Courtesy of the Joe Lefkowitz Pitch F/x tool

I don’t think Soriano’s only problem is his slider, though. He seems to have much less control of all his pitches, as he’s walked eight batters already this year compared with 14 total last season. The fastball he threw to Paul Konerko last night was knee high and over the heart of the plate, despite the fact that Russell Martin was setting up outside. A lack of control was the same problem that got Soriano in trouble during the game he blew against the Twins: he couldn’t locate his fastball and missed his intended location on the majority of his pitches. Soriano is missing the zone 5% more often in 2011 than in 2010, and he’s getting a first pitch strike 8% less often. Simply put, I don’t think he has a good feel on where his pitches are going right now.

Also, there’s possibly some bad luck mixed in with Soriano’s poor results. He’s having lots of balls drop in for hits right now (.333 BABIP) and letting a large amount of runners score (61% LOB%). While BABIP and LOB% can be influenced by a pitcher’s skill level – if he’s missing his locations, it’s more likely a batter will crack a hard hit – there’s also this to consider. I mean, really now?

For Yankees fans, Soriano’s control problem is a mixed blessing. It’s infuriating as heck to watch Soriano continue to miss with his pitches, but at least it’s not something more serious like a drop in velocity (which could signal an injury) and it should be a problem Soriano can fix going forward. How soon? Well, that’s impossible to say. Until it happens, though, at least Brian Cashman can thumb his nose at Hank Steinbrenner and say, “I told you so!”