Instant replay: What can go wrong?

We have full-scale instant replay this year -- well, except for balls and strikes, the "neighborhood" play at second base, foul tips, balks, checked swings and other judgment calls like the infield fly rule.

Unlike reviewing home runs, which has been done using monitors at the ballpark since August 2008, the new system will use a central command center in New York City, where umpires (and video technicians) will review plays and feed the results back to the umpires on the field, similar to the NHL system for reviewing goals.

The rules: Each manager is even given at least one challenge. If his first challenge is successful, he'll receive a second one, but no more than two challenges per manager can be used in a game. If a manager has used up his challenges, from the beginning of the seventh inning the crew chief can initiate a review as well.

Simple enough, right? What can go wrong? Well ...

1. Delays and stalling

When I was at spring training for a week, I saw a few challenges issued. The review process did work fairly quickly and seamlessly, never more than a couple of minutes, and the fans didn't seem to mind the delay. During one challenge, a pitcher did take a couple of warm-up tosses, but in general the replay pause wasn't much longer than the time Josh Beckett takes between pitches.

The bigger potential issue will be stalling by managers. This wasn't a big deal in spring training because nothing was on the line, but I suspect we'll see some strange shenanigans once the real games begin. When issuing a challenge, a manager is supposed to leave the dugout and issue his challenge to the umpire (there will be no flag tossing as in the NFL). But there appears to be a gray area here.

If a manager goes out to argue a call, how long before the umpire demands to know whether he's issuing a challenge? Teams will be allowed to monitor replays from the clubhouse and have some sort of relay system to alert the manager on whether to challenge, so I suspect we may see a lot of arguments in which the manager keeps looking back into dugout for the bench coach to scratch his armpit.

2. The "extra-out" play or other loopholes

The Rays were practicing this play early in spring training. The situation: Runner on second with two outs, close play at first base for the third out. Manager Joe Maddon instructed his team to throw home for the "fourth" out if the runner kept rounding third base -- just in case the play at first is reviewed and the batter declared safe. Likewise, he's instructed his runners to keep heading home on such a play.

You can envision the first time the batter is called out at first base and the first baseman flips the ball back to the mound or into the stands thinking the inning is over, only to have the run count when the batter is ruled safe. The manager on the short end of that review isn't going to be happy.

Other loopholes will seemingly appear as well. Maddon told his team to come up with scenarios. One controversial play will undoubtedly be the neighborhood play at second, when the shortstop or second baseman doesn't actually touch second base while attempting to turn a double play. That play isn't supposed to be reviewable -- but force plays are. So what if a fielder doesn't come close to touching the bag on a double play and the runner is still called out? That's still a force play. But it's also a neighborhood play. See where the headaches can come in?

I'm sure we'll see other crazy plays like that scenario. Fan-interference plays are reviewable, but fan-interference plays are also notoriously tough to judge, even after watching the replay several times. I think we'll still end up with a lot of inconclusive evidence results.

3. They may still get it wrong

Instant replay doesn't mean all the calls will be corrected. Look no further than the botched home run call this past May in an A's-Indians game. Replays clearly showed that Adam Rosales had hit a game-tying home run in the ninth inning for Oakland, but crew chief Angel Hernandez said the replay was inconclusive and the A's ended up losing the game.

Anyway, there is one more really good thing about all this: Clubs can show all close plays on the stadium video board, even if the play isn't challenged. That, I think, is something way overdue. (Sorry, umpires.)