THE BOOK--Playing The Percentages In Baseball

I’m a little unclear about the situation. If they’re playing deeper than they would for a typical batter because Cust is more likely to hit the ball there (don’t know if that’s true), then that’s fine. If they’re playing deeper to prevent a double, then obviously it’s idiotic in that particular situation.

By the way, do you guys adress the “no doubles” defense in The Book? I’m really going to have to buy the thing.

I’m going to have to agree with Frank; from your description, I don’t see what’s wrong with that, assuming that the defense was aligned to best defend wherever the batter is likely to hit the ball.  But I assume your objection is that playing back increases the chances of a single, which would make the score 7-5, and thus bring the potential tying run to the plate?

FrankM and LAWBH: by “playing deeper than normal against this particular batter” I’m pretty sure MGL meant “playing deeper than they play against Jack Cust in normal situations” (and not “playing deeper on this at-bat than they do against normal batter")… I think that’s causing some confusion.

Anyhow, I take it that what’s radically wrong with this is that the correct defense in this situation is whatever defense minimizes the probability that the A’s score 3 or more runs; defense in a normal situation (e.g., where a double-play is improbable / not in effect, a winning run is not on 3rd w/ less than 2 outs) should minimize run expectancy, which is done by aligning the defense so as to maximize the probability of getting the batter out; and maximizing the probability of getting the batter out is what minimizes the probability that the A’s score 3 or more runs in this situation.

So actually, it’s possible that playing deeper than they normally do against Cust could be the right thing to do, but that’d only be the case if their normal defense against Cust was radically wrong!

Infield (corners mostly) and OF defense (depth) positioning is based on the relative value between a single and an extra base hit.  In a “normal” situation (mostly early in a game), a single is worth around .5 runs, a double .8, and a triple 1.0 run.  Anytime those relative values (WE actually and not RE) change, you change the depth of the OF and how close the 1st and 3rd basemen play to the lines.  (No, we did not look at that in The Book).  When the batter is NOT the tying or go ahead run in the last inning, the single is worth almost exactly the same as a double or triple (the only difference being the possibility of the GDP with a runner on 1st), or home run of course. Therefore you ALWAYS play shallower than normal.  If the extra base hit is more valuable than normal, again, relative to the single, like 2 outs and no one on in a one run or tied game, or a runner on 1st and 2 outs, you ALWAYS play deeper in the OF (and closer to the line on the corners in the IF).  And yes, I am talking about as compared to where they normally play the batter - of course.

There does not need to be an analysis of how many singles, doubles, etc. occur with first and third base guarding the lines or not, in order to figure out whether guarding the line is correct or not.  It is ALWAYS correct to “guard the lines” (and shift the 2B and SS over a little) when the double (and triple) is worth more than usual as compared to the single.  Exactly how much to guard the lines is another story.

The important point is that as the relative value of the events in baseball changes, the positioning of the defense should ALWAYS change, insofar as that positioning affects the relative number of singles and extra base hits allowed. As well, the hitting and pitching approach should ALWAYS change.

In yesterday’s Royals game, the no doubles defense bit them in the ass. The outfield was playing way deep to stop the ball from getting in the gap. Sizemore blooped one; Dejesus came in and dove for it but missed. Next pitch Sizemore scored from 2nd on a single to tie the game with two outs in the 9th.

The announcers were more critical of DeJesus taking a chance and letting Sizemore take 2nd on that play instead of playing it safe and keeping him at first. Guarding the lines is something I grew up with and understand; the playing deep to ‘protect the gaps’ is something new for me (at least I don’t remember it). Is that type of defense backed by the numbers?

Paul, as I said in my last post, the positioning of the OF, as with guarding the lines, does NOT have to be backed up by the numbers.  Start with a “normal” (say the beginning of a game) positioning (depth) for the OF, given the batter, pitcher, wind, etc.  Now, as soon as the the extra base hit becomes more valuable as compared to the single, then the OF MUST play deeper.  They will allow more singles and fewer doubles, but since the singles are now worth a lot less than the doubles, the defensive team gains something (win expectancy) over a normal positioning.  If the single at some point in time becomes equal to an extra base hit, such as the last inning when the batter does not tie or win the game, then the OF MUST play closer then normal, as an extra base hit over their heads is the same as a single. Etc.  As I said, the position of the fielders should always change as the relative win value of the various offensive events changes throughout the game.  It is obvious in which direction (out or in) the OF positioning changes.  Now, in order to know exactly how much to change, you need to do some analysis of where balls land, etc.  Not only should the OF play in when a single is worth the same as an extra base hit, but you would expect that the hitters should be trying for more of a singles type swing (as opposed to an extra-base hit type of swing), which would cause the average batted ball to be hit less far, another reason for the OF to play in.

I thought this kind of logic was obvious (hence the title to this thread), but maybe not…

What you are talking about is state of game positioning.  And you are certainly correct that an outfielder should not play deeper than “normal” in the situation you described.  But an outfielder should also change his position based on the count, the likely pitch type, and the pitcher’s tendencies and current effectiveness.  It is possible that those factors caused a deeper positioning.