Max Scherzer has not been himself lately. The reigning American League Cy Young winner is 1-1 with a 5.11 ERA in his last four starts, with just one outing of seven innings or longer. Opposing hitters have a .714 OPS during this stretch, and Scherzer's season-long ERA has climbed from 2.98 to 3.25.
While some may be concerned about Scherzer's recent struggles, there has been one common theme between these four starts (other than them being bad): all four came on the road. In fact, Scherzer has struggled on the road all season long, masking some Cy Young caliber numbers from his 12 starts at Comerica Park. How big is the difference? For starters, Scherzer's home and road ERAs are nearly a full run apart, at 2.77 and 3.61, respectively.
The difference in Scherzer's ERA splits is much greater than his advanced metrics, and his FIP is actually better on the road thanks to a lower home run rate. However, Scherzer's xFIP -- which controls for home run rate, useful for smaller sample sizes -- indicates that he has been slightly better at Comerica Park.
That slight difference in xFIP does not tell the whole story, though. Scherzer has allowed harder contact away from Comerica Park -- or as best we can tell, based on the discrepancy between his batted ball splits. Opposing batters are hitting line drives at a 22.4 percent clip on the road compared to a 19.7 percent rate at home. He is allowing a slightly higher fly ball rate on the road, which is slightly problematic considering how bad the Tigers' outfield defense has been. Meanwhile, Scherzer's ground ball rate has been higher at home, leading to a huge difference in batting average on balls in play.
Unfortunately, I don't have the ability (or free time) to look into Scherzer's pitch location on balls in play to determine exactly why we're seeing this discrepancy in batted ball splits. Is he leaving the ball up in the zone more often on the road? Is his pitch selection different at home? Are opposing hitters really making harder or softer contact in different ballparks? There are several questions that we simply cannot answer due to a lack of information (batted ball velocities, in particular).
One interesting nugget I found while researching Scherzer's splits is the stark contrast in opponents' stolen base success on the road. In away games, Scherzer has allowed 10 stolen bases in 14 attempts, a 71.4 percent success rate. At home, opponents are just two of six, a 33 percent success rate. While Scherzer's higher on-base percentage allowed on the road -- .303, compared to .268 at Comerica -- can partially explain the difference in stolen base attempts, the relative success is a mystery. Perhaps Scherzer is not as comfortable holding runners on an unfamiliar mound, or he isn't as likely to throw over to first in another stadium. Or maybe this is just a product of the small sample we are looking at.
If anything, the most amazing part about Scherzer's home numbers is that they are still spectacular despite his worst outing of the season coming at Comerica Park. On June 17th, Scherzer allowed 10 runs in four innings against the Kansas City Royals, which ballooned his season-long ERA from 3.05 to 3.84 at the time. We won't crunch all of the numbers with that start removed, but Scherzer's home ERA is 1.75 in his other 11 home starts. He has given up five runs in his five starts at Comerica Park since that meltdown outing.
Overall, Scherzer's splits are an encouraging sign for tonight's game, especially given the fact that first place is on the line. However, they are not predictive of future results, especially considering how close his home and road splits have been throughout his career. Still, they should not be ignored, especially given how significant they appear to be in 2014. The Tigers can put themselves in position to benefit from Scherzer's strong home record if they skip fifth starter Kyle Lobstein with Thursday's off day, which would push Scherzer up to start on Sunday against the Cleveland Indians.