Chan Ho Park's dominance

Lately, Chan Ho Park has been impressing me out of the Yankees' bullpen. His season started out horribly, with a few high-profile meltdowns against the Boston Red Sox, but he's really started to put it together recently. He's had good control all year, and now the strikeouts have come along --- his K/9 is up to 7.71, and his K/BB to 4.00. He has started to miss bats consistently, which was not the case at the beginning of the year. Check out his cumulative whiff rate for 2010:

Starting with a two inning relief appearance on May 31st, when he induced 9 swings and misses against a weak-hitting Indians lineup, the whiffing has really taken off. For the whole year, here is how each pitch breaks down:

	Pitch#	Swing#	Whiff Rate
FF	77	29	.069
FT	67	23	.130
SL	97	53	.396
CH	47	21	.429
CU	37	10	.200
	325	136	.272

Park's repertoire includes a four-seamer, a two-seamer, a slider, a changeup, and a curve. I'm pretty sure there are two kinds of sliders --- a harder cutter-like one, and a slower slurvier one, but it's hard to say, particularly since I haven't seen any pitch grips from Park. For now, I'm lumping the sliders together.

I wouldn't be surprised if Park's success would lead to a promotion in Joe Girardi's bullpen pecking order. Joba Chamberlain is currently the primary setup man, and David Robertson appears to be right behind him, but Chamberlain's recent lack of dominance and Park's recent surge could very well lead to a shake-up in the bullpen.

Gameday data is from MLB Advanced Media; it can be easily accessed through Joe Lefkowitz's invaluable tool.

Other stats are from the similarly invaluable fangraphs.com.