Xander Bogaerts’ Hot Bat and Cold Glove by Jay Jaffe June 29, 2021 Xander Bogaerts was right in the middle of the action as the Red Sox swept the Yankees this past weekend, going 6-for-11 with three doubles while either scoring or driving in eight of Boston’s 18 runs. The 28-year-old shortstop is in the midst of his best offensive season, though as his performance in Friday night’s win served to remind viewers, his defense hasn’t been so hot. Indeed, Bogaerts had an adventurous game in the series opener at Fenway Park. After mashing a two-run first-inning double off Domingo Germán and coming around to score himself to run the lead to 3-0, he made an error that loomed large in the top of the second, helping the Yankees tie the game. With one out and runners on first and second, Gio Urshela hit a hot 98.6 mph grounder to Bogaerts’ right, a ball that could have extricated starter Martin Pérez from a jam with an inning-ending double play. Bogaerts ranged over to stop the ball but couldn’t pick it up cleanly, and once he did pick it up, he threw behind the runner to third. All hands were safe, leaving the bases loaded; one out later, all three runs eventually scored, unearned. Bogaerts failed to convert two other balls into outs, a 112.7 mph hot smash off the bat of Giancarlo Stanton in the third inning, and a 75.1 mph dribbler by Urshela in the ninth; both went as infield singles. By the time the latter occurred, the Red Sox had retaken the lead, 5-3, but afterwards Bogaerts expressed relief that his initial miscue hadn’t cost the team the game, saying, “I messed it up big time. That was a rough feeling for me right there […] I’m the happiest guy that we won today, to be honest with you. Because, man, it could have gotten ugly. These guys picked me up big time tonight.” Bogaerts has done more than his share of picking up his teammates this season. Through Sunday — the cutoff point for all of the stats herein — he had hit .330/.391/.557, which placed him fourth in the league in batting average, fifth in wRC+ (154), and sixth in both on-base and slugging percentages. All of those figures are career highs, and if you needed another reference point as to the league-wide downturn in offense, it’s worth noting that Bogaerts’ wRC+ is 13 points higher than in 2019, when he hit a very similar-looking .309/.384/.555. This is the fourth season in a row in which Bogaerts has posted a 130 wRC+ or better. He’s hit a combined .305/.375/.538 (139 wRC+) in that span, ranking third in the majors in average, ninth in slugging, 15th in wRC+ and 17th in OBP. By our version of WAR, which uses UZR as its defensive component, he’s fifth at 17.3, though by Baseball-Reference’s version, which uses DRS — where he’s consistently been in the red — he’s a still-impressive 11th at 15.5. I’ll get to his fielding and the discrepancies in his value below, but his offense is worth a closer look. First off, he’s not exactly scalding the ball; his 88.8 mph average exit velocity is his lowest mark since 2017, placing him in just the 38th percentile, while his 39.8% hard-hit rate is good for just the 44th percentile. He’s better with respect to his barrel rate (10.4%, 67th percentile) and xwOBA (.375, 86th percentile), but as he’s done throughout the Statcast era, he’s outperforming his expected numbers by a substantial margin. Here’s the picture since 2018: Xander Bogaerts by Statcast Season GB/FB GB% EV Barrel% HardHit% AVG xBA SLG xSLG wOBA xwOBA 2018 1.22 43.3% 90.6 9.4% 41.5% .288 .276 .522 .490 .373 .361 2019 1.04 41.2% 90.4 7.6% 42.0% .309 .266 .555 .468 .390 .349 2020 1.27 46.0% 89.0 8.6% 36.8% .300 .257 .502 .471 .368 .339 2021 1.13 39.8% 88.8 10.4% 39.8% .330 .298 .557 .508 .403 .375 Total 1.13 42.2% 90.0 8.8% 40.8% .305 .273 .538 .480 .384 .356 Bogaerts has outperformed Statcast expectations by 32 points when it comes to batting average, a gap that ranks fourth among the 205 players with at least 1,000 PA in that span. Similarly, his 28-point outperformance in xwOBA ranks eighth and his 58-point outperformance in slugging percentage is 11th. Some of those gaps may be related to Bogaerts’ speed, which ranks in the 66th percentile this year and has ranged from 71st to 75th in the three previous seasons. Some of it may be park-related, though it’s worth noting that of the six other Red Sox who meet the 1,000 PA threshold, only Christian Vázquez is more than 15 points ahead of his xBA or his xwOBA, and only Vázquez and Rafael Devers have exceeded their xSLG at all. At the 500 PA threshold, a few more Red Sox have gaps that approach those of Bogaerts, but none surpass him. Red Sox Statcast Differentials, 2018-21 Player PA AVG xBA Avg Dif SLG xSLG SLG Dif wOBA xwOBA wOBA Dif Xander Bogaerts 1810 .305 .273 .032 .538 .480 .058 .384 .356 .028 Michael Chavis 586 .242 .212 .030 .422 .378 .044 .306 .282 .024 Brock Holt 662 .286 .257 .029 .407 .368 .039 .336 .315 .021 Alex Verdugo 526 .290 .267 .023 .454 .424 .030 .347 .329 .018 Christian Vázquez 1232 .261 .241 .020 .410 .384 .026 .307 .292 .015 Eduardo Núñez 676 .255 .251 .004 .366 .336 .030 .277 .269 .008 Rafael Devers 1752 .279 .271 .008 .514 .492 .022 .354 .348 .006 J.D. Martinez 1856 .301 .288 .013 .557 .558 -.001 .388 .386 .002 Andrew Benintendi 1328 .273 .266 .007 .437 .443 -.006 .340 .343 -.003 Mookie Betts 1320 .319 .306 .013 .578 .583 -.005 .412 .416 -.004 Jackie Bradley Jr. 1319 .238 .239 -.001 .418 .425 -.007 .319 .325 -.006 Mitch Moreland 873 .255 .250 .005 .489 .494 -.005 .347 .355 -.008 Minimum 500 PA with Red Sox, 2018-21. All statistics through June 27. One factor that’s contributing to Bogaerts’ big season — and to some extent, his Statcast overperformance — is that he’s pulling the ball a career-high 53.4% of the time, about 11 points above both last year’s mark and his career norm. He’s also hitting grounders on just 39.8% of his balls in play, his lowest mark since 2014. All of that translates into more pulled fly balls, which rank among the juiciest fruits of the batted ball tree; this year, batters are hitting .426 and slugging 1.498 on such balls. Bogaerts’ 35.9% pull rate on his flies is about 11 points ahead of his career mark and nearly 16 points ahead of last year’s mark. On those pulled fly balls, he’s hitting .538 and slugging 1.731; those balls account for nine of his 13 homers, up from four (on just 12 pulled fly balls) last year, though he set a career high with 24 such homers on 58 pulled flies in 2019. Of course, for a right-handed hitter who calls Fenway Park home, pulling a fly ball means taking aim at the Green Monster. Bogaerts has seven such homers at home, six more than last year, and half of his 2019 total. That total of 14, incidentally, is tied with Nomar Garciaparra (2003), Kevin Youkilis (2008) and Betts (2016) for the most by any Red Sox player since 2002, as far back as our batted ball splits go (David Ortiz’s high was 13, in 2007 and ’16). In other words, Bogaerts is on pace to match this mark in a season where offense is comparatively lower, fueling his career-best season with the stick. Here’s a supercut of Bogaerts’ Monster shots from this season: The picture isn’t so sunny when it comes to Bogaerts’ defense. UZR holds him in higher esteem than DRS does, but as UZR doesn’t account for infield shifts — which DRS handles at the team level — I tend to give it less weight in my evaluations of infielders, particularly when the DRS numbers jibe with Statcast’s Outs Above Average numbers, which in Bogaerts’ case they do. Here’s how his last four seasons look: Xander Bogaerts’ Defense Season Innings UZR DRS OAA 2018 1183.1 1.1 -8 -4 2019 1368.0 1.1 -9 -11 2020 438.0 0.3 -4 -2 2021 597.0 0.6 -10 -11 Of the 37 players with at least 1,000 innings at shortstop over the past four seasons, Bogaerts isn’t just the low man, he’s practically an outlier, as his -31 runs is nine below the 36th-ranked Jorge Polanco, and 13 below the 35th-ranked Amed Rosario. Via the component breakdowns visible at Baseball Reference (Air, Range, and Throwing, which join with the team-level Positioning for what Sports Info Solutions now calls the PART System, applicable to their data from 2013 onward), Bogaerts’ biggest deficit this year is his throwing, which has been eight runs below average already, though only 12 below average over the four seasons. Range-wise, he’s four runs below average this year, but 19 below for the four seasons. It’s worth noting that Bogaerts’ bad numbers at shortstop go all the way back to his 2014 rookie season; he’s 60 runs below average during that time, which isn’t quite Jeteresque — he’s never had a season below -11 DRS, whereas the Yankees captain had eight such seasons over the final 12 years of his career — but it’s dead last among the 71 players with at least 1,000 innings at the spot, 19 fewer than the 70th-ranked Polanco and 23 fewer than the 69th-ranked José Reyes, though both of those players are/were much worse on a per-inning basis. Players this consistently subpar generally don’t stay at shortstop for this long. Via Statcast, Bogaerts’ -11 OAA this year is second-to-last in the majors, ahead of only Eugenio Suárez (-12), who should have stayed at third base; for Bogaerts, that translates to -8 runs. The details within the system tell us, among other things, that Bogaerts is nine plays below average when it comes to moving to his right, and three below average when coming in, but average when moving to his left. For 2018-21, Bogaerts’ -29 OAA outdoes only Didi Gregorius (-38); that translates to -22 runs. Again, the bulk of Bogaerts’ woes are in going to his right (-28 OAA). If you’re wondering about the man to Bogaerts’ right, Devers, his metrics aren’t exactly robust either; his -20 DRS for the 2018-21 period is the major’s fifth-worst from among the 34 players with 1,000 innings there, though his -5 OAA is merely the 11th-worst. Devers has a +9 OAA going to his left in that span, towards the hole, and -12 OAA to his right, towards the line. This year, Devers is average according to DRS, though his -4 OAA is the majors’ fifth-worst. All of which is to say that the left side of the Red Sox infield is a shaky one, a fact reflected by the team’s AL-worst .654 defensive efficiency, 18 points below the next-lowest ranked team and 37 points below the league average. That weakness is offset by the offense the pair provides (Devers has a 141 wRC+) but it’s a vulnerability just the same, and when considering Bogaerts’ value, it’s something to take into account. In most situations, he’d be a candidate to move to third base, the position he played for 53 games in 2013 and ’14, but with Devers there, and under club control for two more seasons — and considerably less expensive ($4.575 million this season versus Bogaerts’ $20 million), things are more complicated. It will be interesting to see how the intermittently cost-conscious Red Sox handle the situation if Bogaerts exercises the opt-out he has after 2022. Even based on his less-than-stellar glovework, he’d likely be a 4-5 win player entering his age-30 season, due for some kind of raise. That bridge will be crossed in due time. For the moment, Bogarts is a big reason why the Sox have rebounded from last year’s last-place, 24-36 finish in the AL East to share the league’s best record at 48-31.