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Beginning on Tuesday, Major League Baseball will commence a pilot program in the Single-A Florida State League that will allow teams to challenge check-swing calls using limb-tracking technology, according to the Wall Street Journal. Observant readers may recall that MLB initially experimented with this technology as part of last year's Arizona Fall League. 

Here's a look at how the challenge process played out in the AFL:

Our Matt Snyder chronicled in 2019 how MLB's rulebook has no official guideline on check swings, making it one of the easiest targets for criticism. Does the bat have to cross the plate? Do the hitter's wrists have to break?

Technology is allowing MLB to change that on some level. As Baseball America reported last fall: "If the bat's barrel is judged to have traveled more than 45 degrees past its final stopping point, then it is judged a swing. If it moves less than 45 degrees, then it's not a swing. It is not clear which way the call would go if the barrel lands at exactly 45 degrees."

To be clear, this is a pilot program and there's no guarantee that it ever expands beyond this. On paper, anyway, the proposed system would seem to make a lot of sense, and MLB has had success in experimenting with these kinds of programs before, however -- including with the automated strike zone challenge system that could be implemented at the MLB level as early as next season. Still, the league is cautioning to take this for what it is: a test drive to see if further experimentation is worth the league's time.

"This is an early step in our testing process," MLB vice president of baseball operations Joe Martinez told the Journal. "At this stage, we are determining whether the technology works for this purpose and experimenting with different ways of weaving it into the game."