Navigate to Baseball Savant’s outs above average (OAA) leaderboard and you’ll see a familiar face atop the rankings: Harrison Bader. The 24-year-old has found his name in national headlines because of his stellar defensive play.
To put into context how good Bader has been, the only other outfielder with 20 OAA is the Braves’ Ender Inciarte. You could argue Bader has been more impressive than Inciarte because the Cardinal has seen 143 less opportunities in the outfield.
The OAA metric is cumulative, adding and subtracting catch probability values based on whether an outfielder made play or not. It’s not a rate-based statistic like batting average or strikeout rate. Make a play with a 75 percent chance of being caught and you’re debited .25. Miss the same ball with a 75 percent chance of being caught and you’re credited .75. Total all these up and you have an aggregate OAA number for a given player. (Mike Petriello does a great job of explaining this in further detail.)
Bader is the only player inside the top five outfielders based on OAA with less than 250 chances in the outfield. Every other player has more than 300. This characteristic of OAA highlights how exceptional Bader has been in his depressed amount of opportunities to catch and exceed players with around 40 more games started.
Statcast’s rollout of directional OAA allows us to improve our understanding of Bader’s elite defense.
More than 60 percent of Bader’s aggregate outs above average have been on balls in front of him and in to his right. It’s no coincidence that three of his most commonly viewed catches since July are all on balls in front of him.
Even though Bader was in right field for the play above, he was coming in and to his right. Statcast’s OAA metric unfortunately doesn’t differentiate based on position (yet).
Bader’s play in Miami borders the line between coming directly in and coming in and to his left. Statcast doesn’t seem to have specifications on where the line is between these two arbitrary points. Regardless, another fantastic play by Bader on a ball in front of him without being too picky.
Once again we have Bader going in and to his right.
Bader is the only player inside the top five on the directional OAA leaderboard with more than 50 percent of his added value on catches in front of him. Billy Hamilton excels on balls back and to his left or right. Inciarte moves extremely well laterally. Adam Engel’s ability to rob home runs shows in his chart and nothing seems to land over the left shoulder of Lorenzo Cain. The graphic below shows Bader’s directional advantage compared to other elite defenders in baseball.
So why is Bader one of the few adding such value on balls in front of him?
An initial thought might his propensity to play deep and prefer coming in on balls as opposed to going back. But this hypothesis fails to hold up to scrutiny. Bader’s starting position is 317 feet deep, exactly what Statcast cites as the league-average starting position for a center fielder.
The answer might simply be that Bader has an extremely quick first step—evidenced by his otherworldly sprint speed—or that his ability to track balls in front of him is better than those over either of his shoulders. It’s clear Bader’s defensive success is different than others.
Marcell Ozuna is another outfielder we can learn more about by looking at his OAA. With an OAA of 3, Ozuna sits near players like Cody Bellinger and Kole Calhoun. Below is a look at Ozuna’s directional OAA chart, and frankly, what most average outfielders look like from a directional OAA perspective.
Ozuna isn’t as aesthetically pleasing as Bader to watch in the outfield. Most worrisome is his arm, which has lead some to some speculation he’s battling a shoulder injury. Fangraphs’ defensive value metric isn’t a proponent of him either. But from an OAA perspective, Ozuna has been better than the average outfielder.
Part of this may be because of how many extremely difficult plays he is seeing in left field.
Five-star catches are those with catch probabilities between 0 and 25 percent. This is an arbitrary bucket Statcast uses to determine which plays are the toughest for an outfielder to make relative to others. Ozuna has seen the most five-star catch opportunities in baseball with 32.
Given Ozuna’s neutral defensive ability, he has only made one of these catches. Adding in the context of how hard some of the plays presented to Ozuna are for the average fielder results in Ozuna’s expected catch percentage.
This metric is another Statcast OAA component that aggregates all the plays a defender is presented with and calculates what percent of plays the average outfielder would make. Ozuna’s expected catch percentage is 84 percent. You interpret this number by saying the average outfielder catches 84 percent of the balls Ozuna has seen.
The median expected catch percentage sits at 87 percent for all qualified outfielders. Ozuna’s 84 percent ranks 80th out of 83 qualified players. We can infer a lot of the balls hit to Ozuna this season have been difficult plays.
This creates some difference between Statcast’s OAA metric and other defensive value metrics like Fangraphs. Per Fangraphs defensive runs saved metric, Ozuna is a below-average defender. If you’re relying on OAA, you can make the case he is slightly above average. While Fangraphs metric takes into account more variables and is interpreted in a much different way than OAA, it’s not hard to understand both sides of the is-Ozuna-a-good-defender argument and land somewhere in the middle.
Defensive value is still difficult interpret, even for analysts. Eno Sarris confirmed this point earlier in the season when he broke down why Manny Machado was great as a third baseman and terrible as a shortstop. Sure infielders are different than outfielders, but for one, shifting has caused sample sizes to shrink. With the propensity for outfield shifting and shading as teams invest more in spray charts, the year-over-year predictability of defensive value could become cloudier as other variables influence outcomes.
Kevin Kiermaier was considered one of the best defensive outfielders for consecutive season and has only been one out above average better than Ozuna this season. Kevin Pillar lit up the world with mystifying catches last season and is now only a neutral defender according to OAA.
What 2019 holds for both Bader and Ozuna remains to be seen. For now, there’s nothing wrong with appreciating who the Cardinals have patrolling two-thirds of the outfield.