O'Sullivan Moves to the Left

Sean O'Sullivan (KCA), right-handed pitcher, found a way to fool left-handed batters this season.  In 2010 they hit .247 against him with some power, slugging .428.  This season, lefties managed just a .177 BA against Sean, with a .226 slugging percentage, as a home run is the only extra base hit they collected. 

What is O'Sullivan doing differently?  One thing that stands out is his increased walk rate against lefties.  While the BA against dropped 70 points, the OBP against him only dropped 16 points.  Sean traded walks for extra base hits.  While a high walk rate isn't a good idea overall, for Sean so far, discretion is the better part of valor.

O'Sullivan also changed the movement of his pitches.  He throws a hard sinker and a slider (although the sinker doesn't seem to sink that much).  The following chart shows the movement of those two pitches against left-handed batters:

Sean O'Sullivan, sinker/slider movement, 2010.The hard sinker (the large red area above the horizontal line) tended to move away from lefties.  The slider moved down and in.  In 2011, the movement of both pitches shifted in:

Sean O'Sullivan, sinker/slider movement, 2011.So a pitch that used to tail away from lefties now tails in on them.  The slider moves farther in on them than before.  So a batter used to reaching for one of these pitches is now going to find the ball hit off the handle instead of the sweet spot.  It strikes me that this improvement might not last.  Once LHB get used to this movement, they should be able to hit it as well as last season.  Eventually, O'Sullivan may want to mix in both sinkers, so batters can't prepare for one or the other.

Which Pitchers are Really Getting Squeezed?

Earlier in the week we took a look at which pitchers have been squeezed the most based on total pitches called balls within the PitchFX established strike zone.  While it appeared that pitchers like C.J. Wilson (TEX) and Jon Niese (NYM) have been getting a tight strike zone, the truth is that these pitchers tend to stay around the strikezone with the majority of their pitches.  In fact, C.J. Wilson leads the league in called strikes within the strike zone:

(Data from all 2011 games through May 10th)

So in reality, while pitchers like Wilson do lose a lot of called strikes on the borders, it's mostly a product of the volume of pitches they locate there.  In fact, through Tuesday, Wilson was leading all pitchers in total called strikes, regardless of location, with 194.

If we really want to see which pitchers have had a tough time getting calls from umps, we need to look at the percentage of called strikes out of all taken pitches within the strike zone.

 (Data from all 2011 games through May 10th - Min. 40 taken pitches in the strike zone)

Wilson still cracks the top 50, but he's far from the most squeezed pitcher in the league.  Mariners' closer Brandon League is not getting the majority of close calls so far this season.  The league average for called strikes in the PitchFX defined strike zone has been around 77%, meaning umpires have called 23% of pitches in the zone balls.  Of course, the majority of these are borderline pitches as the following graphic shows:

All MLB Called Balls in Strike Zone (Click to enlarge)

League's missed strikes consist of 18 pitches, the majority of which were thrown to the bottom of the zone.  Batters have taken only 42 total strike zone pitches against him, so his "squeeze rate" is mostly a product of small sample size.  However, when we filter the list down to starters....

(Data from all 2011 games through May 10th)

Among starters, Wilson and Niese still near the top of the list of pitchers getting squeezed. And perhaps Nelson Figueroa would still be pitching in Houston if we had robot umpires.

So we've seen which pitchers have not gotten the majority of close calls so far this season.  In an upcoming post, we'll look at pitchers that have benefited most from expanded strike zones.

David Ortiz Pulling Less

David Ortiz (BOS) hit six home runs so far this season, but only pulled half of them to right of centerfield.  While Ortiz always showed good power the other way, especially pounding the wall at Fenway, he appears to be going to left quite a bit this season.  The reason comes down to a shift in his power.

David Ortiz, in play slugging, 2008-2010.Note the very hot slugging area down and in.  If you divide the strike zone into thirds, top to bottom, Ortiz hits home runs to all fields in the top to thirds, but strictly pulled the ball in the lower third in this time frame.  Down and in is the traditional place for lefties to hit long drives, as they can get a nice upper cut swing on the pitch.

In 2011, that low power isn't there yet.

David Ortiz, in play slugging, 2011.His power lies mostly in the top half of the zone, the area where he is most likely to drive the ball the other way.  Pitchers know to avoid that area, but the mistakes there are hit for doubles or outs.  We'll see if that keeps up, and if pitchers start to take advantage of a spot that might have turned into a weakness.