F/X VisualizationsJanuary 15, 2010
The Tigers and Pirates Sign Probable Closers
By Dave Allen

Yesterday the Tigers and Pirates signed their probable closers. Both teams had question marks at the back-end of their bullpens and found free agents who should have no problem sliding in to the closing roles.

Octavio Dotel

The Pirates -- who had non-tendered Matt Capps leaving their closer position empty -- signed Octavio Dotel. Using a fielding-independent pitcher-evaluation framework that gives pitchers credit for strikeouts, ground balls and avoiding walks (a framework Rich used to rank pitchers back in February), Dotel succeeds in spite of giving up a lot of walks and not getting many grounders by striking out just under 11 batters per nine innings.

Although he also throws a slider and curve ball, Dotel throws his fastball almost exclusively. Last year he threw it over 82% of the time and you have to go back to 2003 to find a year he threw it less than eight times out of ten. Relievers who throw a fastball that often usually bring the heat -- think David Aardsma, Mike MacDougal or Matt Thornton -- but Dotel's fastball averages just 92 MPH. In fact among the ten relievers who throw a fastball most often Dotel has the slowest fastball.

Still this slow fastball is very good . Batters miss a quarter of the time they swing at it, compared to an average whiff rate of just 14%. The result is that over the past three years he is in the top fifteen among relievers for whiff rate (or the lowest fifteen for contact rate).

Part of the reason for this is Dotel pitches up in the zone where batters whiff more often, though rarely hit grounders. I broke the zone into bins and compared the fraction of his fastballs in each bin to the average RHPs fastball to RHBs, the more red the color represents bins where Dotel throws fastball more frequently and the blue less.
Dotel has a consistent swath, from up-and-in to down-and-away, where he throws his fastball. In that swath he throws the ball more often than the average righty and outside he throws the ball less. This is a pretty good place to be, as up-and-in and down-and-away are the most successful locations for a fastball.

The Pirates get a very good relief pitcher in Dotel: his career ERA out of the pen is 3.11, supported by a FIP of 3.36. This should make him a solid closer. (Thanks to Rich for noting my error, including his innings as a starter in his ERA, here.)

Jose Valverde

Valverde has a good pedigree of closing games for the Diamondbacks and then the Astros. He should take the Tigers' closing role, as they had three flame throwers, Ryan Perry, Daniel Schlereth and Joel Zumaya, who can rack up strikeouts but give up too many walks.

Valverde is a little bit better than Dotel. He strikes out just as many batters but is a little better at limiting walks and gets a few more grounders, though still is predominately a fly-ball pitcher.

Valverde brings the heat with a 96-mph fastball, but mixes in a splittler which he throws about a quarter of the time. The splitter is a very good pitch. He throws it slightly more to lefties, and the pitch, like a changeup, has a very small platoon split. In fact over the past three years -- before that he did not throw it as often -- he has had small to negative platoon splits.

Also, while his fastball is an extreme fly-ball pitch, getting just 31% balls in play on the ground, the splittler, which 'sinks' in comparison to his fastball and is thrown lower in the zone, gets 57% ground balls per ball in play. So the pitch keeps him from being as extreme a fly-ball pitcher as Dotel.

Valverde is also a very good relief pitcher, he solidifies the back-end of the Tigers bullpen and should be a good closer. Still some found the price, a two-year 14-million dollar deal and a draft pick, a little high.


Question: "and the pitch, like a changeup, has a very small platoon split"

I'm thinking this is a mistake or I misread it -
Don't change ups have a spectacularly bad platoon split? I can't remember whether its against same handed or opposite batters that change ups are good, but aren't they good against one and awful against the other...?

Johan Santana, FX, is very notable because his changeup is so good he throws it to both handed batters... Right?

Nice job, Dave. I like the up-and-in and down-and-away display for Dotel. Visually appealing and informative.

By the way, Dotel is better than 3.60-3.80 as a reliever. His career ERA out of the bullpen is 3.11 (vs. 5.61 as a starter). His K/9 (11.7 vs. 8.9) and K/BB (3.03 vs. 1.90) are much better as well.


What I mean by platoon split is the difference in results of a pitch between same-handed and opposite-handed batters. Changeups, unlike fastballs or sliders, show no platoon split with similar results to both same-handed and opposite-handed batters. Fastballs and sliders are much more effective against same-handed batters. Because of this most pitchers throw changeups to opposite-handed batters, where fastballs and, especially, sliders are not as effective. I showed this in a past article. And John Walsh found the same results in his 2008 Harball Time Annual article.

Santana's changeup is so good that he throws it often to all batters.

Rich, thanks for noting that oversight on my part; I forgot about his time as a starter.

Paralysis by analysis. I forget, how many Angels can dance on the head of a pin? Please graph and chart.

Nice article! The graph is great. It seems to suggest that Dotel has great control with his FB. I wonder if & how it would be possible to describe such control with a pitch in a stat...

Also, is there a reason why the graph appears as the mirror image of a strike zone? Any reason why we would not want to view this graph as a regular strike zone, or would the be misleading in some way?