A Ground Ball Revolution? by Justin Stofferahn June 1, 2021 It has been an odd year for the Chicago White Sox thus far. The club is leading baseball in pitching WAR behind the dominating trio of… Carlos Rodon, Dylan Cease, and Michael Kopech. Major injuries have and will keep Luis Robert and Eloy Jimenez out of the lineup for much of the season, and their most productive bat to date is a 28-year-old who did not have a major league hit entering the season. But potentially weirder than all that is the way in which Chicago has amassed one of the best offenses in the early portion of the season: the ground ball! Entering May 28, the White Sox were second in MLB with a 114 wRC+, fourth at 5 runs per game, and second in wOBA at .330. This offensive success is not unprecedented, as last year’s Sox featured a high-power offense as well. White Sox Offense: 2020 vs. 2021 Category 2020 2021 wRC+ 113 114 wOBA .334 .330 Runs/Game 5.10 5 OBP .326 .343 ISO .192 .149 GB% 45.4% 48.9% BABIP .314 .317 2021 data as of May 27 What does stand out is the lack of power from this year’s team. Chicago has the sixth-fewest homers and a league-leading 48.9% ground ball rate (league average is 43.5%). If that rate were to stand for the remainder of the season, it would be the seventh-highest ground ball rate since FanGraphs batted ball data started being collected in 2002. The White Sox also have a 8.9% average launch angle that would be the sixth lowest in the Statcast era. Chicago’s grounder-centric offensive success stands in stark contrast to the other nine clubs that round out the 10 teams with the highest grounder rates since 2002. Top 10 Ground Ball Teams Season Team GB% wOBA wRC+ HR Ranking 2015 MIA 51.9% .302 91 29 2005 MIN 50.0% .312 89 24 2007 MIN 49.9% .317 91 28 2017 MIA 49.5% .325 101 19 2015 ATL 49.4% .296 84 30 2014 MIA 49.1% .307 95 24 2021 CHW 48.9% .330 114 24 2004 PIT 48.7% .314 85 26 2012 MIN 48.7% .313 95 27 2016 MIA 48.7% .309 95 29 Average 49.48% .313 94 26 2021 data as of May 27 One commonality between these clubs is their lack of power. Every team on the list finished in the bottom third in homers with the exception of the 2017 Miami Marlins, who thanks to 59 homers from Giancarlo Stanton and 37 from Marcell Ozuna, finished 19th. Of course this should not come as a total shock since outside of the occasional Carlos Gomez or Chris Denorfia inside-the-park homer, grounders are not a ticket to generating power, whether it be home runs or extra-base hits. In fact, the home run explosion of recent years has rendered the grounder even less valuable than it once had been, as the batting average on fly balls since 2017 is higher than on grounders. Results on Batted Balls 2017-2021 Batted Ball AVG SLG OPS Grounder .236 .258 .494 Line Drive .685 .904 1.589 Fly Ball .244 .743 .986 One thing to note on the distribution of batted ball types is that the difference between the team with the best line drive rate and the lowest is generally three percentage points or so, while that difference grows to around 10 percentage points for ground balls and fly balls. Thus teams generally seem to swap grounders for flyballs, and fittingly, the White Sox have baseball’s lowest fly ball rate at 30.2%. Just to hammer home this point, of the teams with the 25 highest ground ball rates between 2002 and 2020, the average wRC+ of those teams is just 91. Only four of those teams had a wRC+ of 100 or more: the 2017 Marlins (101), 2015 Giants (104), 2012 Cardinals (106), and the 2014 Dodgers (112). If you add the White Sox to a scatterplot of ground ball rate and wRC+ for every team between 2002 and 2020, they are a pretty clear outlier. So how have the White Sox turned grounders into a weapon of offensive success? It starts with something every stodgy baseball fan would love: hustling to first. Chicago leads baseball with 52 infield hits that have showcased a mix of luck and speed. The fleet-footed Tim Anderson and Nick Madrigal have collected eight and seven infield hits respectively, while the sneaky quickness of 245-pound Yermín Mercedes and his .378 BABIP have allowed the slugger to pick up six infield hits, including beating a throw from gold glover Anthony Rendon during the season’s opening days. Outside of their success beating out those throws, Chicago is not heads and shoulders above the rest of baseball when it comes to offensive production on grounders. Rather, their offensive output has been a product of creating strong value across all three batted ball categories. This combined with the league’s fourth-best walk rate gives Chicago the highest on-base percentage (.343) in baseball. Just to top it off, the Southsiders are one of baseball’s better baserunning teams, generating the second-most BsR (5.7) off the strength of the team’s ability to take extra bases and avoid double plays. White Sox Production on Balls in Play Batted Ball Type wRC+ wRC+ Rank Grounder 47 4 Line Drive 348 11 Fly Ball 178 5 Data as of May 27 Chicago’s hitters are likely to generate less grounders going forward. Through April, reigning AL MVP José Abreu had a ground ball rate of 58.2% while Silver Slugger Yasmani Grandal was hitting grounders at a 56.1% clip. Both have career grounder rates below 46% (Grandal has been under 40% the last two seasons) and so far in May, Grandal’s ground ball rate has been just 23.5% while Abreu’s is a more familiar 46.2%. Similar results can be seen team-wide as Chicago’s league-leading grounder rate of 52.1% in March-April has dropped to 45.4% in May, which is still the eighth-highest in baseball, but it underscores the team’s quirky first month and that the improvement could continue. 2021 White Sox Batting Leaders Player GB% BABIP wRC+ Hard Hit % wOBA xwOBA Adam Eaton 55.7% .245 91 41.2% .312 .304 Andrew Vaughn 42.2% .291 110 48.9% .324 .348 José Abreu 52.9% .294 132 53.8% .357 .381 Leury García 56.6% .314 64 30.2% .257 .264 Luis Robert 35.3% .433 131 39.7% .325 .325 Nick Madrigal 60.8% .322 117 18.7% .291 .273 Tim Anderson 62.3% .367 108 41.2% .322 .307 Yasmani Grandal 46.6% .135 126 54.2% .348 .382 Yermín Mercedes 42.5% .378 155 30.6% .392 .353 Yoán Moncada 39.1% .393 136 42.7% .364 .390 Players with 100 or more plate appearances as of May 27 However, the White Sox are likely to remain one of baseball’s higher ground ball teams. Anderson (62.3%), Madrigal (60.8%), and Leury Garcia (56.6%) have the three highest grounder rates among White Sox hitters with 100 or more plate appearances and all three have produced above average ground ball rates for their careers (although Madrigal’s is just 72 games long). At first glance, Anderson’s .367 BABIP would seem a bit high, but since 2019, his BABIP has been .393 over 826 plate appearances and his hard hit rate this season is up nearly six percentage points from 2020 to 41.2%. Statcast metrics paint an interesting picture that would suggest White Sox run production has been relatively sustainable. Their .256 batting average is eight points higher than their expected batting average of .248, suggesting some luck in generating hits. However, Chicago’s .405 slugging percentage is 10 points below its .415 xSLG. This all translates to a .330 wOBA and a nearly identical .332 xwOBA. As the season progresses, the Sox will still need to rediscover the long ball, as recent history has shown homers equal wins. According to a piece by Rob Mains on the proliferation of the long ball, “In 2017, teams that failed to homer won only 29.7% of their games. That rose to 31.0 in 2018, fell to 27.3 in 2019, and rose to 31.8 in last year’s short season.” Unfortunately for the unwritten rules of baseball, Chicago’s success might require Yermín to swing at some more 3-0 counts.