Following up on my previous post about the infield fly rule, lets get to the bottom of the zero-sum game that ensues when there is a fly ball in the infield. Let’s suppose the bases are loaded and there are no outs.
The infield fly rule is an artificial rule under which the batter is immediately called out and the runners are free to remain standing on base. Wikipedia recounts the usual rationale:
This rule was introduced in 1895 in response to infielders’ intentionally dropping pop-ups to get multiple outs by forcing out the runners on base, who were pinned near their bases while the ball was in the air.[2] For example, with runners on first and second and fewer than two outs, a pop fly is hit to the third baseman. He intentionally allows the fly ball to drop, picks it up, touches third and then throws to second for a double play. Without the Infield Fly Rule it would be an easy double play because both runners will tag up on their bases expecting the ball to be caught.
I would argue (as do commenters to my previous post) that there is no reason to prevent a double play from this situation, especially because it involves some strategic behavior by the defense and this is to be admired, not forbidden. But aren’t we jumping to conclusions here? Will the runners really just stand there and allow themselves to be doubled-up?
First of all, if there is going to be a double play, the offense can at least ensure that the runners remaining on base will be in scoring position. For example, suppose the runner on second runs to third base and stands there. And the batter runs to first base and stands there. The other runners stay put. Never mind that there will now be two runners standing on first and third base, this is not illegal per se. And in any case, the runner can stop just short of the base poised to step on it safely when the need arises. What can the defense do now?
If the ball is allowed to drop, there will be a force out of the runners on third and first. A double play. But the end result is runners on first and third. Better than runners on first and second which would result if the three runners stayed on their bases. And careful play is required by the defense. If the force is taken first at second base, then this nullifies the force on the remaining runners and the runner on third would be put out only by a run-down, a complicated play that demands execution by the defense. The runner could easily score in this situation.
If on the other hand the ball is caught, then the runer on second will be put out as he is off base. Another double play but again leaving runners on first and third.
So the offense can certainly do better than a simplistic analysis suggests. They could allow the double play but ensure that no matter what the defense does, they will be left with runners on first and third.
But, in fact they can do even better than that. The optimal strategy turns out to be even simpler and avoids the double play altogether. It is based on rule 7.08H: (I am referring to the official rules of Major League Baseball here, especially section 7)
A runner is out when … He passes a preceding runner before such runner is out
According to this rule, the batter can run to first base and stand there. All other base runners stay where they are. Now, a naive analysis suggestst that the fielder can get a triple play by allowing the ball to fall to the ground and using the force play at home, third, and second. But the offense needn’t allow this. The moment the ball touches the ground, the batter can advance toward second base, passing the runner who is standing on first and causing himself, the batter, to be called out. One out, and the only out because according to rule 7.08C, this nullifies the force so that all the baserunners can stay where they are, leaving the bases loaded:
if a following runner is put out on a force play, the force is removed and the runner must be tagged to be put out.
Given this option, the fielder can do no better than catch the ball, leaving the bases loaded. No double play. The same outcome as if the infield fly were called. So the designers of the infield fly rule were game theorists. They figured out what would happen with best play and they just cut to the chase.
But just because best play leads to this outcome doesnt mean that we shouldn’t require the players to play it out. When one team is heavily favored, we don’t call the game for the favorite just because we know that with best play they will win. To quote a famous baseball adage “that’s why they play the game.” The same should be true for infield flies. There’s a lot that both sides could get wrong.
As a final note, let me call your attention to the following, perhaps overlooked but clearly very important rule, rule 7.08I. I don’t think that the strategy I propose runs afoul of this rule, but before using the strategy a team should make certain of this. We cannot make a travesty of our national pastime:
7.08(i) A runner is out when … After he has acquired legal possession of a base, he runs the bases in reverse order for the purpose of confusing the defense or making a travesty of the game. The umpire shall immediately call “Time” and declare the runner out;
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May 17, 2009 at 8:19 am
Matt
Another situation: one out, a fast runner on first, and a slow runner at the plate, who pops up in the infield. Why not let the ball fall, force the fast runner out at second, and allow the slow runner to reach first safely? This exchanges a slow runner for a fast runner who may steal second, but it is never done. But the slow runner also never passes the fast runner at first, invoking the rule about passing runners, so the defense is left with the option to play the strategy I mentioned.
May 19, 2009 at 12:43 am
Aaron
Matt makes a good point. I would say the reason teams don’t do this is that the player to let the ball drop will get a fast-ball thrown directly at his head the next time at the plate.
May 20, 2009 at 11:07 am
michael webster
I suspect if we knew the history of the in field fly rule, you would find that these very strategies had been tried at one time or another. After all, this is a sport which saw a midget being fielded as a batter, precisely because of his impossibly small strike zone!
Be fun to read the commentaries and thinking reported here:
Click to access Infield_Fly_Rule.pdf
June 17, 2009 at 7:18 pm
David
Hey Matt, Melvin Mora of the Orioles just successfully tried your strategy today vs. the Mets. Gary Sheffield hit a pop-up to third and let it fall to force out the faster Ryan Church who was on first base.
July 14, 2009 at 7:16 pm
The Infield Fly Rule, or: Unharnessed Shenanigan Opportunities « The Elephant Seal
[…] far more complex – there has been some amazing game theory on the IFL, discussed at length here by Jeff Ely of Cheap Talk. The basic theory revolves around the idea that with careful […]
October 16, 2010 at 7:08 pm
Sameer
It’s not about game theory its about intention. They want the game to be played as intended. A ball is hit to you, you field it. You don’t intentionally let it drop and come away with an extra out. Basically it was “we don’t like people intentionally dropping balls” as it goes against the spirit of the game. Hence, they decided to make the letter of the law match what they considered to be the spirit of the law.
You may be thinking “well people can still drop foul balls when its advantageous to do so, so isn’t that against the spirit of the law also?” (such as when it would allow a runner to tag up in a close game). Well not really, because you are trading the guarantee of the out for the possibility of saving the run. You are taking on a risk for potential gain.
August 4, 2011 at 12:25 pm
cliff lebrub
is a infield fly ball alive in the air or after it hits the ground can runners advance before ball hits the ground
October 5, 2012 at 10:59 pm
The Infield Fly Rule « Cheap Talk
[…] I wrote about it here. I had a look at the video and it was the right call given the rule, but the rule is an unnecessary kludge, and could be eliminated. talk cheaply Top PostsWhy Your Friends Have More Friends Than You […]
April 1, 2021 at 9:27 pm
Rich sell
The simple solution for a revised IFR is in effect on a trial basis for 2021. It is a simple de-facto approach- when an IFR situation goes un-called- it is still allowed to play out to its conclusion and after review, the offensive team
(if not for a tag up or running error) has the option of taking the Result, or, the automatic one out. This maintains the intent of the IFR, without advantaging the defense unduly.
I proposed a similar revision in 1986 by letters to Dr. BROWN, and Mr. Uberoth; and, also to the Little League. But for the past 34 years I cringe at the IFR calls, especially in the Little League