Diamondbacks Gameday Thread, #75: 6/21 @ Brewers

Zac Gallen starts for the D-backs this afternoon in Milwaukee. This would generally be a great thing, to have a Cy Young front-runner on the mound. But there’s just one problem: it’s in Milwaukee. Because Gallen has had some spectacular home-road splits this season. Here’s where we sit after 15 Gallentine’s Days, eight at Chase and seven outside of Arizona:
Home: 7-0, 54.0 IP, 39 H, 7 R, 6 ER, 7 BB, 67 K, 1.00 ERA
Road: 1-2, 37.1 IP, 45 H, 28 R, 24 ER, 12 BB, 33 K, 5.79 ERA
That’s spectacular, Perhaps the most strikingly different number is Zac’s K:BB ratio. At home, it’s 9.57, while on the road, it’s a much more pedestrian 2.57.

Interestingly, he’s not the only D-backs starter this year with an extreme home-road split. Ryne Nelson has a 3.41 ERA at home, but a 7.09 ERA on the road. But otherwise, there have been few cases of Arizona starters having a difference in ERA greater than three. Here’s a list of all the ones I could find, among pitchers with at least seven starts both at home and on the road.

• 2023 Zac Gallen: 1.00 home ERA/5.79 road ERA (4.79 difference)
• 2023 Ryne Nelson: 3.41/7.09 (3.68)
• 2012 Patrick Corbin: 2.92/6.09 (3.17)
• 2009 Yusmeiro Petit: 7.62/4.28 (-3.34)
• 2006 Enrique Gonzalez: 3.88/7.82 (3.94)
• 2005 Shawn Estes: 6.35/3.00 (-3.35)
• 1999 Brian Anderson: 2.97/7.93 (4.96)

At the moment, Gallen’s ERA difference is the biggest in franchise history for 24 years, with only Brian Anderson in the team’s second season exceeding him. Let’s hope the difference becomes smaller for Zac after today’s outing.