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.