Ronald Acuña Jr. and the fight to trust Baseball Savant's Baserunning metric

Ronald Acuña Jr. is having an historic season on the basepaths, but metrics don't seem to indicate that.
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New York Mets v Atlanta Braves / Kevin D. Liles/Atlanta Braves/GettyImages
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A few minor disagreements with Baseball Savant Baserunning

There are a few examples where I think Savant either penalizes Acuña too harshly or penalizes him when he should be penalized at all. This wouldn't skyrocket Ronnie to the top of the leaderboard, but it would get him out of the zeros.

April 17 @ SD: -0.20 for not trying for a double

I don't think penalizing him for not reaching 2B is the wrong decision, but I do think the weight of it is harsh. It's one of the higher penalties for not advancing without being thrown out, and in this single, the Padres' RF had it backed up perfectly.

If this was a -0.05 penalty, I don't think I'd dispute it, but I'm pretty confident Acuña's only hope of reaching 2B is if he was sprinting at top speed out of the box.

April 14 @ KC: -0.19 for not advancing to 3B from 1B

This should've already been overridden. This single was initially called a foul ball, and after review, the umpires placed Olson at 1B and Acuña at 2B. This ended up getting Brian Snitker ejected.

Getting penalized for where the umpires place you is ridiculous.

July 5 @ CLE: -0.19 for not turning a single into a double

Mike Petriello disagrees with me on it, so frankly you should probably side with him, but I'm still going to include it. Ronnie smokes this ball at 113.1 MPH off the bat and Steven Kwan barehands it on one bounce before making a great throw back in.

The broadcast says that Acuña wasn't running super hard off out of the box, but he's still running out of the box and he takes a hard turn around 1B.

Should this be a penalty? Probably? Most balls that hit off the wall should be a double, especially if you have Ronnie's speed. Was it -0.19 runs worth by not making it to 2B? I'd argue it would be slightly less.

What to make of the metrics?

Ronald Acuña Jr. is going to do something historic this season on the basepaths. His ability to steal bases has been incredible, even with the bigger bases.

However, the metrics are probably closer to being right than wrong. There are definitely parts to nitpick, but overall, the Braves superstar hasn't been quite as aggressive in non-stolen base opportunities as he has in past years.

Part of that might just be because he knows he needs to preserve his legs. Why take risky advances where you could get thrown out, or worse, injured? The part is that he could know he could steal anyway. After all, when you can just do this, why not just steal?

The metrics don't think Acuña is a bad baserunner because he's not, they just recognize that the bulk of his value is coming from steals, while other players gain value in other areas.