Didi Gregorius just finished his best month as a Yankee

In yesterday’s victory against the Texas Rangers, Didi Gregorius went 1-4 with a crucial home run to right field in the bottom of the fifth inning. It was the Yankees only earned run of the day and it capped an excellent month for the Yankees 26 year old shortstop, who had just hit a walk-off home run the night before. Gregorius finished June with a .337 batting average and a 135 wRC+. Since joining the Yankees in 2015, it was his highest batting average and wRC+ of any month.

There are a few statistics that might give some insight into the recent success that Gregorius has experienced. First, an increase in plate discipline has resulted in Gregorius making contact with pitches in the strike zone more often. Second, Gregorius has started hitting the ball to opposite field and center field, which has been a big part of his increased batting average.

FanGraphs uses several different statistics to track a player’s plate discipline. When a player is going through a hot or cold stretch, these statistics can help determine if a player is seeing the ball better or making better decisions at the plate.

The first one that is worth looking at is O-Swing% which is the percentage of swings that a player takes at pitches thrown outside of the strike zone. Since becoming a Yankee, Gregorius has swung at 35.5% of these types of pitches. In June of this season, Gregorius had a 33.3 O-Swing%. Even though it’s better than his career rate, this isn’t far off from the last five months, so it’s safe to say that the hot stretch isn’t due to Gregorius swinging at less pitches outside of the zone.

Since it isn’t due to swings at pitches thrown outside of the strike zone, Gregorius’s success might be due to swings at pitches inside the strike zone. Z-Contact% is the percentage of swings at pitches inside the strike zone when contact is made. Pitches in the strike zone are easier to hit than ones outside, so if Gregorius is making contact more often with these types of pitches, he might see an increase in base hits. Gregorius had a 94.8 Z-Contact% in June, his highest ever. It’s far above his 89 Z-Contact% that he’s had as a Yankee. In fact, it rose to above 90% for the first time in May, which coincides with him coming out of his early season slump in April.

The last factor that might be contributing to Gregorius’s success is his recent ability to hit the ball to the opposite field. In June, 32.2% of Gregorius’s hits went to opposite field, the second highest percentage of any month since joining the Yankees. 28.7% of his hits went to center field. This is way up from May when only 18% of his hits went to the opposite field. The ability to hit the ball to all parts of the field is major advantage over the shift. Defenses are much less likely to employ the shift against a player that doesn’t have pull tendencies. Gregorius is benefiting from this, having only seen the shift in 46 of his plate appearances this season.

To summarize, Gregorius just finished his best month as a Yankee because of two major factors. He making contact with pitches that are in zone and they are falling in for hits all over the field. Both of these signs imply that Gregorius has started to become the player who the Yankees thought he would be when they traded for him. As the Yankees head into July, their chances of making the playoffs will increase if Gregorius can keep up the current pace that he is on.