Troy Percival f/x

Hopefully the Cubs won't see much, if any, of Troy Percival.

Percival ended a two year hiatus in June 2007, and we've got PITCHf/x data for Troy going back to July 21 of that year. He's managed to come back from a serious arm problem and his subsequent retirement, so who knew we'd ever have anything for the guy.

In that 7/21/07 game, he threw what appears to be his last change-up of the season. It was hit for a home run. More on that later.

Percival relies on a four-seam fastball. I think his change-up is just a two-seamer, and he uses it fairly regularly now. He's got a slider and a curveball, too.



I suspect he threw more changes in late June/early July in 2007. STATS (via Fangraphs.com) shows 3.9% change-ups in 2007, compared to 12.0% this year. I get 0.3% and 13.3%. Since we're pretty close in '08, the big gap in '07 is likely a result of Percival truly discontinuing his change-up at some point. It could also be that so many games are missing in 2007, and more pitches within games that are in the database, it could also be luck to some degree.

Here's a deeper dive into Percival's numbers.

cfx	L	R	mph	pfx_x	pfx_z	deg	rpm	B:CS	corner%	Sw%	Whiff%	SwOZ%	TaIZ%	HR%	NKS	G:AO
CH	35	6	86.1	-8.2	8.0	225	1,419	1.8	12.20	46.34	15.79	35.00	34.62	2.4	0.556	0.5
CU	45	25	78.2	5.2	-6.9	216	975	4.7	10.00	27.14	21.05	14.55	18.18	0.0	0.455	0.6
FA	261	250	93.1	-6.4	10.7	211	1,644	1.5	11.94	52.05	17.29	34.75	27.08	0.4	0.318	0.3
SL	0	54	86.2	0.0	4.8	181	632	4.8	11.11	57.41	32.26	42.86	12.00	1.9	0.615	0.7
	341	335	90.6	-4.8	8.2	210	1,480	1.9	11.69	49.56	18.81	32.37	26.16	0.6	0.381	0.3

Notice the slider is an exclusive treat for righties, but they almost completely avoid the change-up. He does throw his share of curves to both groups, but not for strikes. The slider is thrown hard, at 86 mph, and looks like he fools a lot of guys by getting them swinging out of the zone. The fastball is good, given how he throws it for strikes and yields just a .318 noK SLG.

The change-up is a bit of a puzzler. The slider, with it's good whiff rate and Swings out of the zone rate, is typical. Even the home run and nkslg are not unusual. The change-up shows a similar pattern of getting hit hard, and chased, but doesn't get many whiffs. He does get a good amount of called strikes, which is worth looking at a little more.

This chart is all of Percival's change-ups to lefties. Hollow circles are takes, filled circles are swings. As always, click to enlarge.



For the most part, he's throwing that change towards the middle/inner part of the plate and letting it move back across. Seems to do the trick. By the way, the home run is the 7/21/2007 discussed above.

Without considering batter hand, the change-up is most likely to be used on a full-count. He chooses it in 19% of the 3-2 counts he gets into. He uses it no more than 9% of the time in any other count. The slider is found earlier in the count, and when he's ahead. Not thrown when he needs a strike. That, in some cases, is the exclusive domain of the fastball.

Here's what he throws in each count. The % is (pitch type) divided by (pitches in that count). It looks like he's willing to give away a pitch in some cases. But, mostly it's fastballs for strikes.

#	B	S	CH	CU	SL	FA
172	0	0	5.8	11.0	5.8	77.3
91	0	1	7.7	22.0	12.1	58.2
39	0	2	2.6	17.9	5.1	74.4
68	1	0	2.9	1.5	1.5	94.1
86	1	1	8.1	8.1	16.3	67.4
69	1	2	4.3	23.2	10.1	62.3
16	2	0	6.3	0.0	0.0	93.8
40	2	1	0.0	0.0	2.5	97.5
55	2	2	9.1	0.0	9.1	81.8
4	3	0	0.0	0.0	0.0	100.0
10	3	1	0.0	0.0	0.0	100.0
26	3	2	19.2	0.0	11.5	69.2

Not too many deep counts. A lot of first pitch strikes helps. Here are outcomes on the first pitch, by pitch type.

#	cfx	S	B	X + HR
10	CH	50.0	50.0	0.0
19	CU	26.3	63.2	10.5
133	FA	58.6	33.8	7.5
10	SL	40.0	40.0	20.0
172		53.5	38.4	8.1

I publish this during the 7th inning of a 2-1 game, Rays ahead of the Cubs. Unless something changes, this post will be timely.