Yankee Stadium broke Sonny Gray. Would Great American Ball Park be any better for him?

As you have likely heard by now, the Cincinnati Reds have been working for some time on acquiring right-handed pitcher Sonny Gray from the New York Yankees. You’ve also likely heard that Gray had a rough year in 2018. You might have also heard that, actually, he was only bad at home, and when he pitched on the road, he was pretty good.

All three of those things are true, but I don’t think that third bit of information does justice to what a dichotomous season Gray had. As a starter at home, he had a FIP of 5.98, which was the worst in baseball. On the road, his FIP as a starter was 2.65, good for the eighth-best in baseball. To better understand that, observe the following chart.

This is a chart of all 137 MLB pitchers who threw at least 40 innings each at home and on the road in 2018, with their road FIP subtracted from their home FIP. On the far right side, you’ll find pitchers whose home pitching performances were far better than their road performances, which is much more common than the inverse. Of the 137 starting pitchers in the graph, 75 of them (55 percent) posted a better FIP mark in their friendly confines. Twenty-five pitchers posted FIP figures at least one run better at home than on the road, as opposed to just 12 who were at least one run better on the road. If Gray’s FIP were just one run better on the road, he would already be an outlier. But he wasn’t. Gray’s road FIP was better than his home FIP by 3.39 runs, the largest such gap in baseball by a long shot. His bar, if you hadn’t guessed, is the one way over on the left, standing tall and menacing over all the others.

Now, FIP is the statistic I personally chose to demonstrate the difference in Gray’s home and road performances, but there are many others that do so with similar vigor. Gray’s home wOBA of .399 was also the highest of any pitcher to throw at least 40 home innings as a starter in 2018, while his road wOBA of .274 was the 32nd-best in baseball. His home xFIP, 5.10, was the seventh-highest in baseball; his road xFIP, 3.27, was the 18th-lowest.

In Yankee Stadium, Gray struck out 6.8 hitters per nine innings, walked 5.3 hitters per nine, allowed 1.7 homers per nine, and held a 6.98 ERA. On the road, he struck out 9.89 hitters per nine, walked 2.8, allowed 0.4 homers, and held an ERA of 3.17. In front of the home crowd, he was worse than Homer Bailey. On the road, he outpitched Gerrit Cole, Blake Snell, and Clayton Kershaw.

As startling as those numbers appear, they do come with a built-in explanation — or, so it would appear. Yankee Stadium is, of course, a hitter’s haven. According to Fangraphs, it was the major leagues’ most hitter-friendly park with regards to home runs in 2017. One shouldn’t be so shocked by a Yankees pitcher finding more success elsewhere than he does at home, because it’s simply much more difficult to limit runs in Yankee Stadium than it is in most other parks.

The issue with that excuse, however, is that it ignores the fact that Yankees pitchers, by and large, pitched pretty damn well at home in 2018. As a staff, New York allowed a .313 wOBA, a 3.76 FIP, and a 3.65 xFIP at home, compared with a .291 wOBA, a 3.50 FIP, and 3.58 xFIP on the road. The road numbers are a bit better, sure, but nowhere near to the degree Gray’s splits suggest they might be. Even when pitching in the close quarters of their home park, the Yankees’ pitching staff often grades out in the top 10 in all of baseball, without even adjusting for park factors. In fact, of the 12 Yankees pitchers to throw at least 20 innings each at home and on the road in 2018, half of them — Luis Severino, C.C. Sabathia, Domingo German, Jonathan Holder, Dellin Betances and Aroldis Chapman — posted a better opponent’s wOBA inside Yankee Stadium than outside of it.

If Gray’s struggles can’t be explained away by simply shrugging your shoulders and saying “hitter’s park,” then there has to have been something deeper that caused him to so often and so completely fall apart in front of the home crowd last season. It’s just difficult to determine exactly what that may have been. And that’s an important question for the Reds to answer, because Great American Ball Park doesn’t operate a whole lot differently than Yankee Stadium. Pitchers with home run issues see their mistakes magnified in Cincinnati, and in 2018, Gray was a pitcher with a home run issue.

Maybe it was the Yankees’ emphasis on limiting fastball usage, though it’s difficult see how that would affect him differently at home versus on the road. Maybe he watched a few too many routine fly balls catch the right gust of wind in a ballpark where that can often be all it takes. Maybe it was the yips.

Even with Gray’s old college coach, Derek Johnson, in the fold as Cincinnati’s new pitching coach, it’s quite a gamble to take a pitcher who struggled so mightily in one of the game’s most notorious hitter’s parks and drop him into one of the game’s other most notorious hitter’s parks. But there’s plenty of reason to suspect there’s a different problem aside from Yankee Stadium’s dimensions that made Gray struggle in 2018. The Reds are betting they can solve it.