(Elsa/Getty Images North America)
Imagine you are a front office member for the New York Yankees. It is the winter after the 2014 season, and you have a monumental assignment: to replace five-time World Series Champion, five-time Gold Glove winner, five-time Silver Slugger winner, Derek Jeter. You look through the shortstops hitting the free agent market, and none of them are good enough or young enough to take over for Mr. November. So what do you do?
You decide to trade Shane Greene, a 25 year-old pitcher who was 5-4 with a 3.78 ERA and 81 strikeouts in 78.2 innings and 14 starts in his first season with the Yankees, to the Tigers in a three team deal. In this deal, you acquire the shortstop of the future for the Yankees: Didi Gregorius, a 24-year-old Dutch player who can speak almost as many languages (Dutch, Papiamento, English, and Spanish) as home runs he hit the previous season (6).
Along with the 6 home runs, Gregorius hit .226/.290/.363 with 27 RBIs. This was your answer to who would replace one of the best Yankee hitters of all-time, and right about now, you are looking like one of the smartest people in baseball.
Gregorius has improved every season he’s been in New York. He hit .265/.318/.370 with nine home runs and 56 RBIs in 2015, .276/.304/.447 with 20 home runs and 70 RBIs in 2016, and .287/.318/.478 with 25 home runs and 87 RBIs last season. This season, Gregorius has taken another massive step forward for New York, hitting .301/.388/.642 with 10 home runs and 30 RBIs in only 34 games, which is a 47 home run and 143 RBI pace. Here’s how Gregorius has become one of the best players in the American League so far this season.
Many players have seen significant improvement as a hitter by becoming more patient at the plate, and Gregorius is no different. According to Fangraphs.com, in 2017, he swung at 40.8% of pitches outside of the strike zone, which was the sixth highest mark in baseball. This season, that number has fallen to 33.3%. This improved plate discipline has helped increase Gregorius’s BB% from 4.4%, which was the ninth lowest in baseball last season, to 13.2% this season.
(Tom Szczerbowski/Getty Images North America)
Although better plate discipline has greatly helped Gregorius improve as a hitter, the biggest reason for his breakout season is his increased tendency to pull the ball. Throughout his career, Gregorius has been a pretty balanced hitter, utilizing every part of the field. Since arriving in the Bronx, he’s pulled the ball to right field more and more every season. According to Statcast, in 2015, Gregorius’ first season on the Yankees, he pulled the ball 35.5% of the time, which is below the average of 40%. This season, Gregorius is pulling the ball 48.2% of the time (Fangraphs says that a pull percentage of 50% qualifies an extreme pull hitter.
Gregorius has increased his pull percentage every season, and teams are starting to shift against him like a pull hitter. Last season, according to Fangraphs.com, Gregorius had 369 plate appearances with no shift and 77 plate appearances against a shift, which means teams shifted on him only about 17% of the time. This season, that number has grown to almost 50%.
So why has an increase in pull percentage had such a significant impact on Gregorius’ performance this season? Most hitters hit the ball harder when they pull it, and Gregorius increasing his pull percentage has helped him increase his hard hit percentage from 20.8% last season to 37.3% this season (according to Statcast). He has also increased his barrel percentage (percentage of batted balls with ideal exit velocity and launch angle) from 3.6% to 9.1%.
Gregorius has also always had success as a pull hitter. Every home run that Gregorius has hit in his career has been to right or right-center field, as you can see by the spray chart below.
(Baseball-Savant)
A lot of people will discredit what Gregorius has done this season because of the short porch in right field at Yankee Stadium. However, taking advantage of the stadium that you play 81 games in per season is smart. Also, Gregorius has been at his best at the plate when he is pulling the ball, so it was smart for him to increase his pull percentage. As you can see in the graph below, Gregorius’ wOBA has followed his pull percentage. Once he got to New York and started to increase his pull percentage, his wOBA increased as well, which shows that Gregorius’ concerted effort to pull the ball more has paid dividends in New York.
(Fangraphs.com)
Didi Gregorius won’t continue hitting at the pace that he has at the start of this season, in fact, he is 0-16 in his last four games. However, his increased power this season can continue if he keeps hitting the ball hard to right field. Although it is impossible for anyone to replace Derek Jeter, the Yankees have hit on another tremendous shortstop.