Home vs. Away: Do Bullpen Decisions Differ in Crucial Moments?

As we take a deep dive into reliever usage for the third article in this series, it’s important to set the stage for what we aim to accomplish. Before breaking down the nuances of how teams deploy their high-leverage relievers in different situations, particularly in the 9th inning at home versus on the road, we should reflect on the broader goal of this project.

Ultimately, this series serves as a comprehensive guide—a book of sorts—on bullpen management. Every team uses its bullpen, every team talks about using it optimally, and every team tries to deploy the right pitchers when and where they are most valuable. However, while there’s no shortage of opinions on the subject—fans, analysts, and broadcasters often praise certain managers as "masters" of bullpen usage—the reality is that hard data and systematic analysis on this topic are far less common.

That’s where this work comes in. I wanted to take a deeper, data-driven look into how teams manage their bullpens, but also keep it simple and digestible. The goal is to move beyond conventional wisdom and anecdotal evidence, breaking down how and why teams use relievers the way they do. This series isn’t just about confirming long-held beliefs; it’s about testing them, identifying patterns, and highlighting strategies that teams may (or may not) be using effectively.

With that foundation in place, this final piece will focus on late game reliever deployment at home vs. away, exploring whether teams manage these high-leverage situations differently based on location—and if so, whether those differences are backed by logic, tradition, or something in between. Lets first jump into how the league plays these situations on the whole.