Chris Tillman Working On A Cutter

Word is that pitching coach Rich Kranitz came to Chris Tillman with the idea of working on a cut-fastball, and that Tillman is going to do so (with an assist from Kevin Millwood, apparently*).

"Chris Tillman has started to experiment with a cut fastball, though he isn't sure whether he'll carry it into the regular season...

"It's something Kranny mentioned to me, that I might want to work on it in the off-season," he said. "I played catch with it and liked it, and I'm going to continue working with it. Who knows? I might shut it down or I might keep it going, depending how I feel in the bullpen. It's going well so far."

Tillman said he needs a pitch that moves out of the strike zone, and anyone who watched his starts with the Orioles last year would probably agree.

"My curveball is a 12-to-6 and stays in the zone a little bit," he said. "It might go below the zone, but they still have a chance to hit it. This is something that moves out of the zone and gets in on the lefties a little bit. It could be useful this year if I do end up throwing it."

Tillman has discussed the pitch with Millwood, noting that the veteran's four-seamer has similar movement.**"

* Veteran leadership!

**Millwood throws a cutter sometimes, which I assume is the pitch Tillman wants to emulate. His four-seamer does have more movement than Tillman's four-seamer, but in the opposite direction of the cutter (in towards righties instead of lefties). If Chris wants to get that kind of action on his pitch, he'd have to work on a two-seamer (also a fine idea) instead.

I think that's a great idea, as I did last year as well. Using Brian Bannister as my inspiration, I thought that maybe adding another type of fastball to get more groundballs would help Tillman out. Plus, it already looked like some of his heaters were cutter-ish to my eye (and the Pitch/FX^ data). Here's a layout of what kinds of movement ranges go with what type of pitches:

I thought it might be interesting to take a look at how Tillman's fastballs from 2009 that were in that cutter area compared to the rest of his fastballs. (Actually, I just used the horizontal movement instead of the circular range, so the "cutters" will be the pitches that had horizontal movement - or, really, horizontal spin deflection - from -2.5 to +3.) Here's his movement graph, with the "cutters" in red and the rest of the fastballs in blue:

Tillman even threw a few pitches that legitimately cut, moving in toward left-handed batters. I do find it amusing that he wants "a pitch that moves out of the strike zone", given that the cutter is relatively straighter than the four-seamer (which runs in on right-handed batters from a righty pitcher). For Tillman, the fastball has quite a bit of "rise" to it, which explains his flyball tendencies. Not a ton of tailing action either. Anyway, a little over 13% of his fastballs were classified as "cutters" here. Moving on; was the location for the pitches different in any way? Here's the graphic against right-handed batters, with "cutters" in red, fastballs in blue, and the strike-zone approximated by the black box:

Not really any difference, with the "cutters" being peppered in there with the fastballs. Tillman generally worked away, and up in the zone. And against left-handed batters:

No real difference here either. Looks like Tillman really tried to stay away from lefties - I can see why he said he needed a pitch to get in on them. The pitches are also even higher in the zone than to righties. Further comparison (keep in mind that the sample sizes aren't large):

	Fastballs	"Cutters"
Velocity	92 mph	92 mph
Whiff Rate	9%	13%
Ground/Air Outs	0.49	0.75
SLG on Contact	.708	.500
HRper1000	42	28

The average velocity was the same for both. Whiff Rate is the complement to Contact Rate, and denotes the percent of the time that a batter misses when he swings at a pitch. As you can see, the "cutter" was more difficult to get the bat on. Ground/Air Outs shows the proportion of ground outs to outs in the air (flyballs and pop outs). It appears that the "cutter" is better at generating groundballs*, which is one of the main reasons for Tillman to start throwing it. SLG on Contact shows the slugging percentage against on balls that the batter put into play. There were 12 home runs hit off of fastballs (corresponding to a rate of 42 per 1000 fastballs thrown) and 1 off of a "cutter" (28 per 1000 thrown), which largely explains the difference. * Though those numbers don't exactly correspond to his overall GB/FB rate. The "cutters" grade out a little better than fastballs across the board, and presumably if Tillman really worked on his "real" cutter then he might be able to get even better results. If that's the case, then adding the pitch to his arsenal would seem to be a good move.