What’s Behind DJ LeMahieu’s Power Outage? by Chet Gutwein September 3, 2021 The Yankees snapped a four-game skid on Wednesday against the Angels to avoid a sweep and stay two games ahead of the Red Sox in the AL wild card race. Gerrit Cole was brilliant, striking out 15 en route to his 14th win of the season. Two-out singles from Luke Voit in the third inning and Brett Gardner in the fourth plated most of the runs for the Yankees, with Aaron Judge adding insurance with a solo shot in the eighth. Perched atop the lineup was DJ LeMahieu, who reached base three times and scored the first run of the game. It’s been a bit of a down year for the veteran second baseman, who earned MVP consideration in the 2019 and ’20 seasons. Not known for his power before that former season, he caught the power bug immediately after joining the Yankees, slugging 36 home runs in 871 plate appearances, good for one home run every 24 trips to the plate. Those aren’t huge power numbers in today’s game, but it’s a much higher frequency of home runs than he managed hitting in Coors Field half the year — three times as often, in fact. This season has gone very differently in the home run department. LeMahieu leads the team in plate appearances (575) and games played (126) but has gone deep only nine times, a rate that’s much more in line with how he hit prior to coming to New York. So what about his performance has changed? For the most part, quality of contact is consistent with what he’s produced in the past; his maximum exit velocity is 110.6 mph, falling between his marks from the ‘19 and ‘20 seasons. What jumps out is his home run-per-fly ball rate. If you’ve been paying attention to LeMahieu the last few seasons, you may have been waiting for this to happen. The power surge that he’s experienced as a Yankee has come in large part due to a doubling in his home-run rate on fly balls. His 30.7 HR/FB% at Yankee Stadium is otherworldly, some 20 points higher than his rate on the road and second to only Ryan McMahon’s home-road splits in that stat. 2019-20 HR/FB% Home/Road Splits Player Team PA HR/FB (Home) HR/FB (Away) Difference Aaron Judge NYY 266 39.5% 30.6% 8.9% Josh Donaldson ATL/MIN 362 36.8% 18.8% 18.0% Jesse Winker CIN 289 36.7% 20.0% 16.7% Ryan McMahon COL 381 36.4% 15.0% 21.4% Christian Yelich MIL 400 35.9% 29.1% 6.8% Yordan Alvarez HOU 204 34.1% 32.5% 1.6% Miguel Sanó MIN 318 32.3% 39.1% -6.8% Fernando Tatis Jr. SDP 298 32.2% 29.4% 2.8% Nelson Cruz MIN 393 32.1% 34.9% -2.8% Derek Dietrich CIN/TEX 171 31.8% 18.2% 13.6% Roberto Pérez CLE 279 31.6% 22.8% 8.8% Jake Cave MIN 160 31.6% 23.1% 8.5% Ian Happ CHC 172 31.6% 22.9% 8.7% DJ LeMahieu NYY 418 30.7% 10.7% 20.0% Joey Gallo TEX 250 30.5% 23.3% 7.2% Minimum 150 plate appearances. Strangely though, and to the dismay of the front office that committed $90 million to LeMahieu for the next six years, his Yankee Stadium home-run rate has fallen back down to 10.9%. That kind of drop is outside of the expected error bars that come with seasonal fluctuations; something else is going on here. Most of LeMahieu’s peripherals are consistent with his body of work as a major leaguer. His hard-hit rate this season sits at 43.6% compared to a career average of 44.6, and his contact rate is at 87.2%, which is right on his career average of 87.1. As a contact hitter with a pretty flat bat path, he is typically near the bottom of the league in average launch angle, and that’s the case again this season, with an average of 4.5 degrees, fifth lowest among qualified hitters. That low launch angle is what makes his power surge in pinstripes so suspect. The friendly geometry of Yankee Stadium explains it somewhat, but many of his home runs are “wall scrapers.” In 2019, his homers averaged 386 feet, the 17th-lowest mark among hitters with at least 10 home runs. As Jay Jaffe pointed out last year, LeMahieu hits a remarkable number of fly balls to the opposite field. Let’s update Jay’s table to include this season: LeMahieu Pull vs Opposite Field Year Pull PA GB/FB Pull GB% Pull FB% Pull SLG Oppo PA GB/FB Oppo GB% Oppo FB% Oppo SLG 2015 98 9.88 81.4% 8.3% 0.327 180 1.32 35.2% 26.7% 0.568 2016 106 6.91 73.1% 10.6% 0.529 184 1.04 32.6% 31.5% 0.568 2017 114 8.3 74.8% 9.0% 0.432 202 1.15 35.3% 30.9% 0.576 2018 137 5.21 72.3% 13.9% 0.518 136 0.76 30.1% 39.7% 0.556 2019 144 8.69 78.5% 9.0% 0.583 174 0.62 25.6% 41.3% 0.719 2020 48 9.25 77.1% 8.3% 0.563 76 1.00 34.2% 34.2% 0.853 2021 107 7.18 73.8% 10.3% 0.491 154 1.04 34.4% 33.1% 0.513 Overall, his batted ball position is more or less the same as previous years, but his distribution of fly balls has changed a bit. Since last season, his opposite-field fly-ball rate dropped from 39.3% to 34.2% for the 2020 season. This year it’s fallen even further to 33.1% to go with a career-low .513 slugging rate on fly balls to the opposite field. For context, let’s take a look at a typical LeMahieu homer. Statcast measured that home run off that bat with an exit velocity of 97.5, a launch angle of 21 degrees, and an estimated distance of 351 feet. You can see that it just barely gets over the wall, but a home run is a home run. Thanks to this excellent analysis from Devan Fink earlier this year, we have a pretty good idea of the type of home runs that have been affected by the new ball. Unfortunately for LeMahieu, his trademark line-drive–opposite-field home runs fall right in the sweet spot. LeMahieu Fly Ball Subsets BBE Subset Estimated Effect of New Ball 2019-20 BBE 2019-20 Homers 2019-20 HR/FB 2021 BBE 2021 Homers 2021 HR/FB 20-24 LA, 104-109 EV -0.18 5 1 20.0% 0 0 0.0% 20-24 LA, 94-99 EV -0.20 13 1 7.7% 2 0 0.0% 25-29 LA, 100-104 EV -0.22 11 6 54.5% 2 0 0.0% 20-24 LA, 100-104 EV -0.34 8 3 37.5% 9 1 11.1% Total 37 11 29.7% 13 1 7.7% SOURCE: Baseball Savant If we’re to interpret this directly, the new ball has potentially cost LeMahieu a few home runs, and while that can be said for most players, because of the way he hits his home runs, it probably hurts him more than most players. If we focus on the subsets of “20–24 degrees LA, 100–104 EV” and “25–29 degrees LA, 100–104 EV,” the new ball took away four homers; replace four outs with those, and his season wOBA goes from .317 to .332. That’s not going to win him a Silver Slugger award this season, but it’s a significant difference. More generally, though, of the 36 homers that LeMahieu hit in ‘19 and ‘20, over half of them sailed over the fence with a launch angle less than or equal to 30 degrees and an exit velocity no greater than 105 mph. This season, only three of his nine home runs fit that description. The league-wide HR/FB rate for such balls has dropped, going from 33.1% in 2019 to 22.3% this season. For LeMahieu, the dip has been even more dramatic, going from 50% two years ago to 10.5%. Take that power boost away, and LeMahieu more resembles his former Rockies self. He’s taken a small step backwards this season in terms of base hits, but some of that could be attributed to some bad luck and a decrease in hard-hit rate; his .301 BABIP is the second-lowest of his career behind only his 2018 season total of .298. That was his final year in Colorado, when he finished with a wRC+ of 87 and 2.1 WAR. Even though he managed elevated power numbers in his first two seasons in pinstripes, regression was overdue. But all is not lost, as he still brings plenty of value to the Yankees’ lineup. Aided by a career-high 10.8 BB%, he serves as a reliable option at the top of the order to set the table for the powerful bats behind him. And despite just barely registering above average in terms of wRC+ (102), LeMahieu’s solid glove and penchant for staying healthy have him on pace for a season-ending WAR in the neighborhood of 3. Pretty good for a guy who’s taken some flak for not meeting expectations at the plate.