Several of you asked for a bullpen version of the “best pitches in the rotation” post, and so here you go. Instead of just the 2011 season I’ve gone back and corralled the last two seasons worth of data for this post. The columns headed by “w” and “w/100″ are the pitch type’s linear weights (representing the total runs that a pitcher has saved using that pitch) and linear weights per 100 pitches (the amount of runs that pitcher saved with that pitch type for every 100 thrown), which provide some level of insight into a pitch’s relative level of effectiveness but should not be analyzed in isolation, as they are subject to the whims of both sequencing and BABIP. I’ve ranked the hurlers by their respective Whiff rates, as the ability to generate a swing-and-miss is probably the most transparent indication of pure stuff.

(Note: This post was researched and written prior to the release of the reclassified PITCHf/x data at Brooks Baseball — which I’ll be chiming in on next week — and the numbers are from TexasLeaguers.com and Fangraphs. Given that relievers typically have less variation in their repertoires than starters, I feel comfortable that the data presented below is mostly accurate.)

Four-Seamer

Rafael Soriano’s generated the highest whiff percentage on the four-seamer out of the six primary members of the Yankee bullpen, though that is probably partially propped up by his excellent 2010. As far as pitch type linear weights go, David Robertson’s four-seamer has been the most effective at 12 runs above average, while Cory Wade’s was most effective on a per-100-pitch basis, at 2.17 runs above average.

Cutter

Without looking at the numbers I’d have assumed that Mariano Rivera would easily lead in cutter Whiff%, but he actually lags both Soriano and D-Rob. Of course, having even an 8.1% whiff rate on a pitch you throw 86% of the time is still absurd.

Slider

For all the crap Boone Logan gets, his slider’s actually pretty outstanding, generating a whiff nearly one out of every four times he throws it. Joba Chamberlain also has a big-boy slider, though at times (cough cough full count cough) he’s fallen a bit too in love with it, occasionally making it painfully predictable.

Curveball

David Robertson has the best curveball in the ‘pen by a pretty substantial margin, though Cory Wade’s isn’t terrible. Joba’s had a decent amount of success with his curve though he throws it pretty infrequently.

Changeup

It’s Cory Wade by a landslide here, though he wins by default as no one else in the ‘pen really throws a changeup. It hasn’t been an outstanding pitch by linear weights, but it was his bread-and-butter in a terrific season for the Yankees in 2011.

During the past year, one of the most frustrating aspects of conducting advanced baseball analysis has been the widening gulf between the reliability of the pitching data supplied by Baseball Info Solutions (and which FanGraphs uses) and Sportvision’s PITCHf/x, the latter of which is near-universally acknowledged as the superior data set (though that’s certainly not to say PITCHf/x is without its own flaws). To the delight of baseball nerds like me, FanGraphs recently went a long way toward rectifying this situation, adding PITCHf/x data not only to the individual player pages, but even more importantly, to the sortable leaderboards, enabling us to make comparisons that were previously impossible unless one wanted to input every individual name into TexasLeaguers.com manually and compile the data themselves in as painstaking a manner as possible.

In honor of the newfound ability to see where our favorite pitchers ranked in relation to their peers, I’ve taken a first pass through last year’s data to see where the members of the Yankees’ starting staff ranked among the 42 qualified AL starters across several categories. Neither Freddy Garcia nor Phil Hughes made the innings cut, which is why they’re not present. I also didn’t evaluate horizontal movement (pfx_x) or vertical movement (pfx_z), as you can’t really rank H-break and V-break in descending/ascending order (though you can try), at least not without first binning by pitching arm, which FanGraphs does not have the ability to do.

It may surprise you to learn that Ivan Nova threw the 7th-most four-seamers in the American League last season, although despite the fact that it’s frequently been derided as a lesser pitch for Nova, he also wound up having the most relative success with it on the Yankee pitching staff, with a 0.46 FF/C, good for 12th-best in the league. It will not surprise you that A.J. Burnett had by far the worst four-seamer in the league, at -2.21 per 100 thrown.

Here’s another interesting Nova nugget: despite the fact that PITCHf/x only has him having thrown a slider 3.7% of the time — a percentage that appears to be incorrect — he had tremendous success with it (which is, of course, something we already knew), putting up a 0.90 wSL/C, good for 11th-best in the AL and second on the team after CC Sabathia. As I and many other shave noted throughout this offseason, Nova’s slider will likely be the deciding factor behind whether he can continue to pitch as effectively as he did in 2011.

CC Sabathia’s sinker was one of the best in the game, ranking second-fastest (93mph), most valuable on an overall basis (2.5 runs above average) and second-most valuable on a per-100 basis (0.41). The only thing that worked for A.J. Burnett last season was his curve, which was worth 10.7 runs above average. And Bartolo Colon, as we saw all season, had one of the best two-seamers in the business, worth 4.7 runs above average, good for 7th-best in the AL.