Is Center Field Cody Bellinger’s Best Position?

Cody Bellinger is in the midst of an MVP-caliber season. His 7.3 WAR is second in the majors, his 166 wRC+ ranks third, and he’s among the league leaders in almost every offensive category. Barring a major surprise (from, say, Anthony Rendon), the NL MVP should come down to him and Christian Yelich. In addition to his incredible production at the plate, Bellinger has improved by leaps and bounds in the field. He’s putting up elite defensive numbers in right field for the Dodgers, and now they’re planning on moving him to center field full-time for the rest of the season.

The inconsistent play of A.J. Pollock in center provoked this move. An elite center fielder in his time with the Diamondbacks, Pollock’s defense has slipped terribly this year (-8 DRS, -5.8 UZR); meanwhile, Bellinger’s defense has improved dramatically this year (19 DRS, 9.8 UZR). The Dodgers are hoping this shuffle will give them the optimal alignment in the outfield in their quest for a championship.

At this point in his career, it’s more accurate to call Bellinger an outfielder than a first baseman. A few weeks ago, his major league time spent on the grass surpassed his time spent on the dirt. When he was drafted out of high school, Bellinger’s defensive scouting reports often mentioned that he had the athleticism to play in the outfield, but only in a corner. Here’s how Bernie Pleskoff described his defensive potential in his MLB.com scouting profile: “If needed, he could be a successful outfielder. I don’t think he has the speed to play center, but I think he could succeed in right.”

The Dodgers began giving Bellinger time in the outfield in 2015, two years after he was drafted. He’s seen time at all three spots and that versatility has definitely benefited his team. After Corey Seager was injured for the year, Bellinger was thrown into center for a little less than 500 innings last year. He played very good defense at the hardest position in the outfield, including making this extremely difficult catch in the World Series:

Here’s how the advanced defensive metrics grade his abilities at each outfield position:

Both DRS and UZR absolutely love his abilities in right. His 19 runs saved per DRS is tops in the majors this year, and his 9.8 runs saved per UZR is second after Mookie Betts. Baseball Savant’s Outs Above Average (OAA) is a little more even in its appraisal of his defensive abilities.

While DRS and UZR are both useful tools, I prefer OAA’s granularity a little more. Statcast uses a ball’s hang time and the fielder’s distance from the ball’s landing spot to calculate a catch probability. From there, we can calculate how many balls a fielder caught and compare that to the average catch rate for similar balls, giving us Outs Above Average. Using directional OAA, we can begin to build a profile for Bellinger’s strengths and weaknesses in the outfield. Directional OAA splits his fielding skill into six segments based on the direction he’s moving to get to the ball’s projected landing point. Here’s how he fared across the six directional slices in his three years in the majors:

His biggest improvement has been on his ability to come in and make plays in front of him. When the ball is hit over his head, he’s been strong at tracking to the left but has struggled going straight back and to the right. Here’s a scatter chart of the balls he’s had to go back on that have fallen in for hits (ignoring directionality):

There’s a smattering of balls in play with extremely difficult or impossible catch probabilities towards the bottom of the chart. The easiest balls to catch that have fallen in for hits anyway were complicated by the outfield wall (the dots outlined in green). Those hits at the wall have an extra amount of difficulty beyond simply getting to the right spot at the right time.

Outfielder Jump is a new Statcast fielding metric, which was introduced this year. It takes three components — reaction, burst, and route — to calculate how good of a jump an outfielder gets on a batted ball hit to him. Unsurprisingly, Bellinger’s ability to get a good jump on the ball gives him a huge advantage in the field. His burst is particularly good, which makes up for his less than ideal initial routes. His sprint speed sits in the 89th percentile so even if his first step is in the wrong direction, he has the ability to make up the ground with his long legs.

Traditionally, center field has been one of the highest positions on the defensive spectrum with first base and the outfield corners some of the lowest. Based on those assumptions, what the Dodgers are asking Bellinger to do is rather risky. He’s shown that he’s an elite defender in right but moving to center could erase all of that defensive value simply because of the positional adjustment and greater difficulty of the position.

Before he left Baseball Prospectus for a job with the Mets, Russell Carleton revisited the assumptions of the traditional defensive spectrum. He concluded that outfielders, no matter what their regular position is, can usually switch between the three outfield positions without serious consequence.

“Emergency center fielders have—and this is not a misprint—performed at roughly the same level defensively as regular center fielders over the years. That could be an artifact of our sample. These might be fourth outfielders or corner guys who are fully capable of playing center, but never get to do it because there’s someone better on the depth chart.”

Carleton goes on to show that infielders who make the switch to outfield have a much harder time adjusting to the new position than an outfielder sliding over to another outfield position. And while the data show that center is the hardest position in the outfield, the drop off from center to the corners might not be as steep as we thought.

The Statcast defensive metrics seem to confirm these revised assumptions about the defensive spectrum (at least when it comes to outfield defense). The implications are especially interesting for Bellinger. His raw abilities give him a great jump on balls hit to the outfield and he’s developed a solid fielding profile based on where the ball is hit. Those skills should transfer no matter which outfield position he’s playing. Reading the ball off the bat and the spin of the ball in flight will take some minor adjustments, but the strong foundation is there. If sliding over to center isn’t going to significantly affect his defensive abilities, the Dodgers may have stashed one of the best center fielders in the game in right field for most of this season.