Buster Posey vs. Fastballs

A reader requested we take a look at how Buster Posey has fared versus fastballs this season.  Contrary to his concern, Posey has actually done well against the pitch in 2011.  He's hit .316 and slugged .456 compared to .284 and .483 prior to this year. 

One reason his average is up on fastballs is because he's hit 9 line drives off them this season, and all 9 have fallen for hits.  However, none of them have been for extra bases, which could be why his SLG% is down slightly.

(Click to enlarge)

From the above graphic, you can see that his power is a bit more spread out against fastballs this season.  Last year, he hit fastballs up and out over the zone extremely well.  In fact, on fastballs in the upper portion of the pitching zone, Posey slugged .565 last season with three doubles, one triple, and four home runs.

Posey has actually had trouble versus off-speed pitches in 2011.  His average is down from .313 in 2010 to .222 so far this year.  Against changeups in particular, Posey has really struggled; his average is down 177 points. 

It's a little early to get hung up on pitch type results, but as far as fastballs are concerned, Posey has hit about as well as he did in 2010.

More Change Ups for Matt Cain

Matt Cain (SFN) altered his pitch selection significantly so far in 2011.  During the previous three seasons, Matt relied on his fastball, working a change up occasionally.  He used the heater 62.1% of time time, with the change tapped 11.6% of the time. The pitch barely shows up in comparison to the fastball:

Matt Cain, break on fastball and change up, 2008-2010.The change is represent by the small tail down and toward a right-handed batter.  In 2011, Cain throws fewer fastballs and more change ups, the change accounting for nearly a quarter of his pitches.

Matt Cain, break on fastball and change up, 2011.The tail stands out more as fastballs are down to 56.4% and changes are up to 24.2%.  Why the change to the change?  During the three previous seasons, Cain's fastball resulted in a .306 wOBA, while his change brought him a .282 wOBA.  In 2011, those numbers are closer, but the change still wins .287 to .293 for the fastball.

Cain didn't stop with just throwing more change ups, he's throwing them farther down and out than before.  In 2008-2010, he threw the pitch for strikes.

Matt Cain, change up location, 2008-2010.This season it's more likely to be out of the strike zone:

Matt Cain, change up location, 2011.It's not clear that this shift really helped Matt, as he's getting more ball on the ground, but giving up more hits as well.  That said, pitchers run the risk of becoming too predictable.  Altering his pattern puts something new in the mind of his opposing hitters, and that works to the pitcher's advantage.

Breaking down Tim Lincecum's Changeup

It goes without saying that Tim Lincecum has one of the best changeups in the game.  Since 2008, batters have only made contact on 55.5 percent of their swings, good for 4th best in the league among pitchers throwing at least 500 changeups.  Lincecum has also induced a high swing rate of 59.0 percent over that period, good for 5th best in the league.  The combination of the two speaks volumes to the quality of his change, as Lincecum has been able to successfully fool batters with the pitch, getting them to both swing and miss frequently.

As can be expected with any changeup, the more downward movement you get on the pitch, the harder it is to hit.  Lincecum's change has averaged 15.8 feet per second of downward velocity when crossing the plate since the beginning of the 2008 season, but when put in play, the ball averaged an entire foot less of vertical movement.

Here's a breakdown of his changeup by vertical movement (PVZ):

Tim Lincecum Changeup 2008-2010

PVZ	P	VEL	CNTCT%	xK%	xBB%	HR%	xwOBA
≤13 ft/s	224	83.4	82.9%	33.0%	13.4%	2.8%	.293
13.1 - 14 ft/s	234	83.2	79.9%	31.2%	10.1%	1.1%	.274
14.1 - 15 ft/s	290	83.3	68.9%	36.7%	7.0%	1.8%	.267
15.1 - 16 ft/s	323	83.4	62.5%	41.7%	7.1%	0.0%	.221
16.1 - 17 ft/s	343	83.4	44.6%	46.3%	7.4%	0.0%	.207
17.1 - 18 ft/s	249	83.7	34.0%	48.7%	10.0%	0.0%	.214
18.1 - 19 ft/s	177	83.4	14.3%	50.8%	10.3%	0.0%	.203
≥19 ft/s	178	83.6	11.9%	46.4%	14.4%	0.0%	.252
Total	2018	83.4	55.5%	41.7%	9.5%	0.7%	.240

It's quite telling based on contact rate alone how much more effective the change is when it has more downward velocity. It's important to note that a changeup with less vertical movement will more often end up higher in the zone, as those with more movement often end up down in the zone. So you're bound to get less contact with changeups that end up scuffing the plate than those that float over the strike zone. But as his expected K-Rate indicates (as well as his overall swing percentage), Lincecum is getting batters to swing at those changeups down in the zone, resulting in a lot of strikeouts.

The plummeting xwOBA that accompanies the increase in downward velocity on Lincecum's change is impressive. With 15 feet per second of movement or more, batters essentially can do nothing with his change. The expected walk rate jumps a bit with more than 17 ft/s of movement, and that is mainly due to the number of those changeups that fall out of the strike zone for balls. However, the actual walk rate on those changeups is around 7.0%, which is still lower than the 8.2% walk rate Lincecum holds on all pitches since 2008.