Community Post: Sir Didi’s Quest for Power

“When I saw him, he reminded me of a young Derek Jeter,” said Kevin Towers, then General Manager of the Arizona Diamondbacks while describing a then 22-year-old Didi Gregorius. Arizona acquired Gregorius from the Cincinnati Reds (in a three-way deal which cost them Trevor Bauer) following the 2012 season. However, after he was unable to beat out prospect Chris Owings for the starting role in 2014, he was traded to the New York Yankees before the start of the 2015 season. New York acquired the then 25-year old Gregorius to replace the recently-retired Derek Jeter at shortstop. He had big shoes to fill, a knighthood from his native Netherlands and 13 home runs in 191 career games. 

 

However, once donning pinstripes, Gregorius went on to hit 20 or more homers in three of his five seasons in The Bronx, and had 16 in 82 games during his injury-shortened final season with the Yankees. And in doing so he became far more than Jeter’s replacement. Gregorius endeared himself to The Bronx to the point that when you look under almost all of his post-win emoji tweets since signing with the Philadelphia Phillies in 2019, you’ll find Yankee fans pining for him. 

 

Through 92 games with the Phillies, Gregorius has 14 home runs, keeping him close to the pace he established in New York. This sudden surge of power was especially unexpected in part because there was no corresponding surge in exit velocity, since Statcast’s installation in 2015, Gregorius has regularly found himself in the the bottom 10th percentile in said stat. Yet still, the potential had always been there. After invoking Jeter’s name, Towers went on to gush about Gregorius, “I was fortunate enough to see Jeter when he was in high school in Michigan. [Gregorius has] got that type of range, he’s got speed, more of a line-drive-type hitter, and I think he’s got the type of approach at the plate and separation to where I think there’s going to be power there as well.”

 

The irony of comparing Gregorius’ defense to Jeter aside, it turns out yes, the power was there as well, but how did Gregorius start actually hitting home runs? Like most lefty bats that arrive in The Bronx, Didi heard the siren’s call of the short porch in right field of Yankee Stadium. Upon his acquisition by New York, all 13 of Gregorius’ career home runs were to right field, but unfortunately for him, he had to play half of his games at Chase field––where it’s 334 feet down the line in right and 413 feet to right-center.

 

Gregorius’ approach didn’t change when he got to the Yankees, but the circumstances and the results did. During his tenure in the Bronx, Didi hit 97 home runs as a Yankee, 54 of them were at Yankee Stadium and all of them were to right field. In fact through his Yankee tenure, every home run he hit went to right. His tendency to pull the ball hasn’t changed since signing with the Phillies after the 2019 season either, though he did hit his first home run to straightaway center earlier this season. 

 

But while Citizens Bank Park isn’t as large as Chase Field, there’s no short porch for Gregorius to take advantage of––making the fact that he’s been able to keep this pace up all the more impressive.

 

And the advanced stats indicate that Gregorius is hitting well above expected. Besides being near the bottom of the league in average exit velocity (bottom 2% of the league during both seasons in Philly), his xSLG and his xWOBA are both well below both league average and his actual numbers––he’s slashing .229/.266/.364. However, it’s been this way since arriving in New York and it hasn’t caught up with Gregorius yet. 

Season	xBA	xSLG	wOBA	xwOBA
2015	.247	.327	.303	.285
2016	.247	.351	.319	.272
2017	.257	.378	.336	.290
2018	.255	.395	.350	.315
2019	.232	.383	.297	.281
2020	.262	.394	.348	.310
2021	.209	.292	.271	.234

 

Gregorius’ home run totals with the Yankees rose as his ground ball to fly ball ratio dropped. In 2015, New York’s assistant hitting coach Allan Cockrell talked about a change they made in his swing that season. “He’s doing some things in the cage that kind of force him to flatten out his bat path a little bit,” explained Cockrell. By 2016 both Gregorius’ both his fly ball rate and his home run to flyball ratio had taken off. 

 

In 2021, Gregorius has fallen just a bit behind last year’s pace––10 in 60 games or 27 in 162, which would have tied 2018’s career high. However, looking at Didi’s own indicators (because standard methods clearly do not work), he may be poised to catch fire shortly. Currently, Gregorius’ ground ball rate is the lowest of his career and his line drive rate is the lowest since his rookie year, so a career-high 47.4% fly ball percentage indicates that he’s doubled down even further. Yet his 8.9% home run to fly ball ratio is his lowest since 2015. 

Season	Team	Level	GB/FB	LD%	GB%	FB%	IFFB%	HR/FB
2012	CIN	MLB	3.33	13.30%	66.70%	20.00%	0.00%	0.00%
2013	ARI	MLB	0.89	21.00%	37.10%	41.90%	16.40%	5.70%
2014	ARI	MLB	0.87	19.60%	37.40%	42.90%	9.60%	6.40%
2015	NYY	MLB	1.31	21.20%	44.70%	34.10%	9.30%	6.00%
2016	NYY	MLB	0.99	19.60%	40.10%	40.30%	10.90%	10.40%
2017	NYY	MLB	0.83	20.00%	36.20%	43.80%	15.50%	12.10%
2018	NYY	MLB	0.93	19.50%	38.90%	41.60%	12.00%	14.80%
2019	NYY	MLB	0.85	18.40%	37.50%	44.10%	15.00%	13.30%
2020	PHI	MLB	0.84	20.70%	36.20%	43.10%	16.00%	12.30%
2021	PHI	MLB	0.76	16.80%	35.80%	47.40%	17.80%	8.90%

Per FanGraphs

 

Delving a bit deeper, he’s been pulling the ball about as much as he was during 2017 and 2018, but that’s still about a three percent drop from last season. Pair this with the lowest percentage of hard-hit balls in his career and it’s almost a wonder Gregorius has four homers this year. 

Season	Team	Level	Pull%	Cent%	Oppo%	Soft%	Med%	Hard%
2012	CIN	MLB	37.50%	25.00%	37.50%	0.00%	100.00%	0.00%
2013	ARI	MLB	36.30%	36.90%	26.80%	20.30%	56.60%	23.10%
2014	ARI	MLB	32.90%	42.80%	24.30%	17.60%	54.50%	27.90%
2015	NYY	MLB	38.50%	35.00%	26.50%	21.60%	55.90%	22.50%
2016	NYY	MLB	37.60%	33.10%	29.40%	19.60%	55.90%	24.50%
2017	NYY	MLB	40.30%	37.40%	22.30%	24.40%	52.40%	23.10%
2018	NYY	MLB	40.40%	36.90%	22.70%	22.50%	41.60%	36.00%
2019	NYY	MLB	42.10%	37.40%	20.50%	20.10%	45.40%	34.40%
2020	PHI	MLB	43.20%	29.50%	27.40%	23.70%	47.40%	28.90%
2021	PHI	MLB	40.00%	35.80%	24.20%	31.60%	49.50%	18.90%

 

With some minor adjustments Gregorius could easily start getting around the ball and yanking it down the line again. With a full 162-game season in front of him, Didi could easily climb his way back to around 25 home runs again this year. Especially with the weather warming up, let those fly balls carry just a little bit further on those humid summer days in Philly.

 

Gregorius’ quest to find power did not take the typical route. According to Statcast’s information, Sir Didi’s home run pace is totally unsustainable, and yet it does just that in spite of what his xWOBA or exit velocity say. Baseball has always been about defying the odds, and with Didi’s power continuing to defy both the odds and logic these seasons since he arrived in The Bronx––his quest––feel more magical. 

 

 

Photo from KeithAllisonPhoto.com | Design by Quincey Dong (@threerundong on Twitter)