Early season dominance

Here are the top 10 pitches in terms of whiff rate (swinging strikes/swings) so far in 2010. Unsurprisingly, all of the pitches are offspeed, either changeups, splitters, or sliders. The data is through May 6th, and I'm using a 50-swing minimum as my cut-off.

MLB Rank	Pitcher	Pitch Type	Swings	Whiff Rate
1	Brandon Morrow	Slider	58	.569
2	Shaun Marcum	Changeup	83	.518
3	Cole Hamels	Changeup	93	.495
4	Roy Halladay	Changeup	59	.492
5	Carlos Marmol	Slider	60	.483
6	Carlos Zambrano	Splitter	55	.473
7	Tim Lincecum	Changeup	130	.469
8	Clay Buchholz	Changeup	58	.466
9	Tyler Clippard	Changeup	50	.460
10	Francisco Liriano	Slider	90	.456

I've only re-classified the pitches of a handful of pitchers, so this is a conglomeration of my classifications and (mainly) MLBAM's. So unfortunately, there will be some mis-classifications. Any input on this front is always appreciated.

A few notes:

Tyler Clippard is having a pretty good go of it so far. Along with his 4 relief wins, 1.44 accumulated WPA, 10.55 K/9, and sparking 0.42 ERA, he has two top-tier whiff pitches --- his changeup, as shown above, is 9th best of all pitches (6th best changeup), and his four-seamer, with a .323 whiff rate, is second best to Matt Thornton's .344 mark.

There is only one curveball that ranks in the top 20 in whiff rate so far this year. Roy Halladay's hook, swung-and-missed at 40% of the time, is the 20th best whiff pitch in the majors.

On the other end of the spectrum: two-seam fastballs seem to have the most trouble getting whiffs so far. The sinking pitches of Kyle Lohse, Paul Maholm, Jason Varags, Nick Blackburn, and Ryan Dempster have all whiff rates under 4%.

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