Coming into the season, the biggest question mark the Yankees had on defense was with the Captain in center field. Sure, Aaron Judge had played center field before — 119 across the previous three years, to be exact — but never before had he been the regular, everyday center fielder across the full 162 game season. Would his success in center field in 2021, 2022, and 2023, during which period he accrued -1 Defensive Runs Saved and 2 Outs Above Average in 924 innings, translate over a full season?

Back in May, the answer appeared to be a resounding “yes.” Roughly two months into the season, Judge had accrued 1 DRS, while Outs Above Average pegged him as perfectly average (i.e., 0 OAA). While a step down from Harrison Bader, arguably the best center fielder of his generation, No. 99 provided competent, albeit unspectacular, defense in center.

Almost three and a half months later, however, the situation has changed. Although Judge has continued to make the highlight reel in center — such as this home run robbery against the Nationals — FanGraphs and Statcast have looked less positively on his prowess in center. Defensive Runs Saved and Outs Above Average each rank him among the worst in the league, with his -6 DRS ranking 20th among the 22 center fielders with at least 700 innings in center, and his -6 OAA 22nd. Additionally, he has yet to make a play categorized as “five star” (catch probability 25 percent or lower) out of 16 opportunities, and just one “four star” play (26 to 50 percent) out of nine.

Much has been made in recent days of Judge’s slump: heading into action yesterday, he had a slash of just .186/.340/.256, with just three extra base hits, in the 12 games since his last home run, which was back on August 26th. While defensive splits aren’t readily available for this stretch (FanGraphs doesn’t let you divide defensive metrics into anything smaller than a season), we can look at some plays in recent games that, according to catch probability, ought to have been outs, but were turned into hits.

On the surface, this looks like a tough play, as Judge slid in an attempt to make the play. According to Statcast, however, this was a routine play, with a 95 percent catch probability. Much like Clint Frazier’s patented diving catches on balls that should’ve been routine plays, it never should have gotten to the point where a slide was necessary.

Statcast does not find Isaac Paredes’ two-run single on Sunday — the only two runs given up by the Yankees during the weekend series — all that egregious, as it had only a 65 percent catch probability. Even so, it does show Judge not getting a great jump on the ball, forcing him to pull up rather early on the ball.

Both of these plays show a growing trend: namely, that Judge is covering less ground in center than he had been. While, again, Statcast doesn’t allow us to get temporal splits on this data, Judge’s 30.5 feet covered in center field is the worst of his career and a full two feet fewer than he covered in 2023 (and three feet fewer than 2022). This puts him 3.5 less feet less than league average, ranked 108 out of the 109 qualifying outfielders, and better only than the Mets’ Jesse Winker. Although it’s impossible from the publicly available data to prove whether this has declined at this time (I would have needed to manually check and record this data on a regular basis throughout the season), the fact that a large number of the one and two star plays that have fallen in for hits come from the last few weeks suggests that Judge has lost a step as the season has gone on.

These trends on defense, combined with his recent slump at the plate, suggest that the grind of the full season as a center fielder is starting to catch up to Judge. Fortunately, the arrival of Jasson Domínguez in the Bronx gives the Yankees an opportunity to give No. 99 some half days off as the designated hitter (and perhaps even some full days off) to get him off his feet and make sure that he’s not worn down for the postseason. While the Yankees have said that Judge will continue to be the starting center fielder and Giancarlo Stanton will still be the primary DH, leaving left field — and Alex Verdugo’s plate appearances — for the Martian, don’t be surprised if we see an alignment similar to the one we saw last night (Verdugo/Domínguez/Soto) on more than one occasion throughout September.