Among Major League Baseball’s vast rulebook is a simple yet obscure rule that’s always present in the action but rarely goes mentioned. It states that should a baserunner pass another live baserunner who’s ahead of him on the bases, he’ll be ruled out.

It’s hardly mentioned because it’s a rule that’s rarely violated. That’s because it’s basically second nature for players at the professional level to be aware of the runners ahead of them.

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As with any rule, there are always some exceptions. Unfortunately for Diamondbacks infielder Deven Marrero, he was the exception on Saturday night during his team’s 9-1 win against the Dodgers. Making it more painful, the rarely seen violation actually cost Marrero a home run.

Marrero, 27, slugged a ball over the fence against Dodgers left-hander Rich Hill for what he thought was a three-run homer. Alex Avila, who was occupying first base, saw it differently. He originally retreated to first thinking the baseball stayed in the yard and was caught by an outfielder.

By the time either player realized what was happening, Marrero passed Avila. Both immediately paused once it registered, then continued rounding the bases. The umpires allowed the play to continue, then changed the call after the Dodgers initiated a review.

It doesn’t seem fair to apply more blame to one player over the other. Avila simply lost track of the ball, while Marrero lost track of Avila. First base coach Dave McKay was overlooking the play too, and he clearly lost track of Avila. Heck, even the umpires weren’t sure enough to call it right away. It should never happen, but it’s surprising it doesn’t happen more often considering all the moving parts involved.

We’re confident it will never happen to Marrero or Avila again.

The home run would have been Marrero’s first in a Diamondbacks uniform and sixth overall in 117 MLB games. Since he made it to first base safely, he was credited with a single. That’s at least good for the batting average. He also gets credit for knocking in both runs.

Still, home runs are what all baseball players dream about. We can’t think of a more painful way to lose a homer than this.

The Diamondbacks hit four home runs that did count in Saturday’s win. Paul Goldschmidt hit his third of the season. A.J. Pollock hit his second and third. Naturally, the other was hit by Avila, which was his first for Arizona.

The Diamondbacks improved to 11-3 with the win. They’re 5-0 against Los Angeles this season.

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Mark Townsend is a writer for Yahoo Sports Have a tip? Email him at bigleaguestew@yahoo.com or follow him on Twitter!

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