Saturday, August 08, 2009
The enemy among us
Mike Fast contends that our spokesperson, the now-groundballing Banny, has to contend with a SS that is not up to speed:


Betancourt can’t field balls hit up the middle on the shortstop side of second base, even if the second baseman can reach them. He can’t field balls hit into the hole. I must be missing some of those “other factors” like defensive positioning and what not, although I’m not sure what positioning gives you problems with balls up the middle and in the hole.
Betancourt is a bad SS, there is no doubt about that. My BZM fielding metric has him as the worst fielding SS over 2005-2008. UZR has him a little wrse than average over that time period but plyaing much worse this year.
But I am not sure that these 3 plays are the best choices to illustrate his lack of range. Gameday has the first ground ball up the middle, the one fielded by the CF, as being at vector -1 degrees, although it looks more like -5 degrees from Mike’s captured image. Either way of all ground balls that get past the pitcher in that sector the SS only fields the ball for an out 24% of the time. From the image and the position of the batter and runner it looks like the ball was hit at at least an average GB speed and perhaps greater which means that even an excellent SS would have had little chance to field that grounder for an out.
The second grounder, the one fielded by the 2B, appears to be in almost the same vector, but much slower. Mike says that Betancourt may have able to make the play so this one appears to be the kind of mistake that happens when the SS and 2B haven’t played together much. Or perhaps the 2B has already figured out that he can’t count on Betancourt’s range and that he should field every ball that he can get to.
The third grounder, the one through the hole to the LF is the one that perhaps Betancourt should have been able to field. Gameday has that one as being fielded by the LF at -24.4 degrees and it probably passed the SS at closer to -22 degrees which appears close to what the image shows. That ball hit by a right haded batter is usually fielded for an out by the SS around 60% of the time. Again we don’t know how hard it was hit. Shows why we need a Hit f/x database and hit ball times to fielders. A good SS probably would have had a chance at keeping that ball in the infield and possibly getting the force.