New Defensive Statcast Stat, OAA Suggests Bryant is Better than Rizzo

We used to look at defense as whomever had the most errors was the worst defender and the least amount of errors meant you were the best defensive player. That wasn’t really the case, and while I’d argue that someone with five errors is likely better than someone with 25, it isn’t that easy.

Errors, a little similar to RBI, is a product of opportunity. If I have a fielding percentage of .995 and another person has a .995 as well, but I had 200 more chances, I would have one more error than the next guy. Or, say I had a single throwing error all season and someone else had seven. But I benefited from a good defensive first baseman and the other guy had a below average fielder at first. That other guy probably had a better defens season than I dis, but I had less errors.

There’s a thousand other factors, like infield type (some are fast and some are slow), more groundball pitchers vs flyball, etc.

It’s the inefficiencies in defensive metrics that cause many stat-heads to continue to create new defensive metrics. Just look at things like UZR or UZR/150. I feel comfortable with those stats, but either can be manipulated by short term production. Proof is with Kyle Schwarber. I’m not sure anyone would consider Schwarber a good defender, and while I’d argue that hes made tons of great strides to be serviceable, but since 2017 he is rated as the second best defensive left fielder in baseball. This is true using UZR, UZR/150, and Fangraphs Defensive Rating.

In another effort to create a more perfect defensive stat, MLB’s Statcast put out Outs Above Average (OAA). This is an interesting stat as it does what it suggests, measures the outs across defenders and averages them against all defenders. Here is how Statcast defines it.

Outs Above Average (OAA) is the cumulative effect of all individual plays a fielder has been credited or debited with, making it a range-based metric of fielding skill that accounts for the number of plays made and the difficulty of them. For example, a fielder who catches a 25% Out Probability play gets +.75; one who fails to make the play gets -.25.

This is the stat that is being passed around showing Javier Baez as the best defensive player. Now, not that I disagree, I think Baez is an incredible defensive player with skills I’m not sure I’ve seen before. But, I do think he can learn to position himself better, use his body momentum to assist with some throws, and minor tweaks that would make perhaps the most dynamic player in baseball, even better.

I was curious about this stat, and I ran a report on all Cubs. I was curious to find out this stat lists Kris Bryant as a better defender than Anthony Rizzo.

I suppose some can say this is a chicken or the egg sort of thing, maybe Rizzo is weighted down because he has to field balls from Bryant, but really it isn’t Bryant’s arm that causes issue defensively. Now, he can put himself in a better throwing position, I find that he stands too upright, too often when he throws. This doesn’t allow for him to explode into the throw, and could cause the ball to sail.

But really, Bryant’s issue is being too tall for a position that requires incredible reflexes. Don’t get me wrong, Bryant has much better reflexes that you, I, or anyone else that might read this, but it is hard to get his body to get to that backhand side on hard smashes down the line. This likely causes Bryant to play closer to the line, giving a larger hole between him and Baez at short.

Rizzo on the other hand has been a very solid defender – but not great. I know he won a Platinum Glove, but far too often these awards haven’t been given out to the best defensive players. In fact, the Platinum Glove is a fan-cebtric award based on only the Gold Glove Award winners. But even the Platinum Glove Award is using SABR Defensive Index to more accurately compare players, giving a useful hand to anyone who votes.

Whether Bryant had a better season defensively than Rizzo is really up for question. Fangraphs suggests Rizzo was quite a bit better (2.9 UZR/150 vs -1.5), but it is difficult to measure across positions. Using OAA, Rizzo ranked 35th among 1B while Bryant ranked 18th among 3B. Using UZR/150, Rizzo was second in baseball and Bryant 15th.

I think I still put more stock in UZR/150 as it seems to show me what my eyes are telling me.

There is quite a bit of data that goes into OAA, but I think it is best used as a supporting tool, being coupled with other defensive metrics, in order to tell a full story. It, like nearly all advanced metrics, isn’t enough to stand alone.