There was a classic neighborhood play in last night’s Sox-Tigers game. And it has me wondering about the future and instant replay.

The scene: Austin Jackson on first base, Jose Iglesias at the plate. He grounds it to Pedroia who bobbles it, then flips it to Stephen Drew at short who tries to start a double play. You can watch the play in real time at the :18 second mark here:

Note that Drew takes that throw pretty far off the second base bag. Here’s a still:

We are all familiar with calls in this situation. In order to keep shortstops and second basemen from being destroyed on close plays, umpires have routinely called base runners out as long as the middle infielder was “in the neighborhood” of the bag when he accepted the throw. Most often it’s a situation in which the fielder skids a foot across second base and takes the throw a second later. It’s a pretty smart instance of latitude, obviously, because you do not want guys having their knees blown out as they try to ensure that the foot is on the bag in every instance.

This one, of course, was more extreme than you usually see, Indeed, it wouldn’t have surprised me a bit if the ump had called Jackson safe here because of how far off the bag was when Drew took the throw. But rather than dwell on it for purposes of this game (it happened, it’s over), I’m more interested in thinking about what could happen with this play, and all neighborhood plays, if it were to occur in a future with a replay challenge system like the one we’ve been told to expect.

If managers can challenge this play, Jim Leyland certainly comes out to challenge it, right? Why wouldn’t he? Unlike last night where any argument he might have made about it would have been pointless, in a replay system he has a chance to get an out back. And if there is replay on it and he did argue, the umpire clearly must rule that Jackson was safe, yes? We could probably live with that — this play was on the extreme end — so probably not too big a deal.

But now picture a more typical neighborhood play when the fielder skids his foot across the bag but takes the throw a second later. Wouldn’t a manager be wise to challenge those too? Like, every one of them? I mean, an out is valuable! Don’t umps have to call it how the replay actually shows it then? The entire point of replay to take out those fuzzy areas of umpire judgment, after all. And if neighborhood plays get challenged and outs get overturned, doesn’t that mean the end of the neighborhood play? And doesn’t that put middle infielders at greater risk of injury?

Of course it’s possible MLB could make a rule that the neighborhood play is not subject to challenge. That would be hard, though, because as it is now, there are still instances where umps do call runners safe if the neighborhood is too big. And there are plays at first base sometimes where the first basemen is given the benefit of taking his foot off the bag early in the interests of not getting stomped on. Where do you draw the line on a matter that, historically, has been part of an umpire’s judgment and discretion?

And if MLB doesn’t say the neighborhood play is exempt from replay, how do managers approach it in real life? It’s hard for me to imagine that managers would actually challenge normal neighborhood plays as a matter of course because, man, that’d be kind of a jerk move. But sometimes one out would be critical and maybe they do? Do they challenge it in tight games but not blowouts? Late innings but not early? How does that work? And does it become a strategic tool for managers? It’ll be interesting to see.

For my part, though, “interesting” does not mean “good.” I want the umpire to maintain discretion in that situation, not have the neighborhood play become something managers can tinker with in order to gain strategic advantage. More broadly, I want umpires and umpires alone to be the ones who decide how rules are interpreted. And if we had a replay system that was instituted and run by umpires (with my preferred “fifth ump in the booth” system), they’d be able to.

With a challenge system, who knows how it’ll go?