In The Lab: Breaking Down Astros Bullpen Usage

It would be difficult to assert that any road trip has gone worse for the Astros. It started with taking one of six games from two of the worst teams in baseball. It ended with a four game set against the division rival Mariners. It is not officially over even as you are reading this, but the damage has been done. The team has stumbled down the standings, three players have moved to the injured list, and one more was sent to Houston for tests on his arm and shoulder.

Three of those four injuries were pitching injuries. In that universe, the study belong takes on an entirely new context. All that being said, Joe Espada took on a ton of criticism last season with his willingness to send his relievers out there for multiple innings. In particular, some wondered if pitching Josh Hader in multiple innings multiple times played a direct impact in ending his season early. It may have been no coincidence that his very last outing was a two inning relief appearance.

If we were giving this a proper study then we would want to study all 30 teams or at least American League teams to determine how often this is happening. That kind of study might come later if this trend continues, but we are comparing the 2025 Astros with the 2026 Astros. In particular, we are looking at the number of multiple inning relief appearances and the numbers of those outings that wound up being scoreless outings. In other words, was it an effective strategy for Espada last season and has it been an effective strategy this season? For our purposes, we are looking at the top seven pitchers in games pitched from last season.

2025 Bullpen Usage

Obviously, any strategy has to be evaluated on two prongs. How effective is the strategy and does the strategy have any long-term lingering negative effects? The first question is an easier question to answer. If a team made it through more than 80 percent of their relief appearances (overall) with a no runs given up then that bullpen has probably done fairly well. People often have unrealistic expectations when it comes to the bullpen. If a pitcher pitches three games in a week and surrenders a run once then he has a 3.00 ERA if all of those are one inning outings. I think most people would take that from all of their relief pitchers and walk away happy.

So, if we are looking at relief pitching in that prism, then we would say that two out of every three outings should be a scoreless outing. That is in effect the break even point. So, as a team they were breaking even more than that on multiple inning outings. Of course, that can be defined as little as 1.1 innings pitched all the way through three or four innings.

This is why many Espada critics focus in on his handling of Hader. Beyond any physical problem, it wasn’t an effective strategy. For someone that was one of the most effective relievers through his injury, he was decidedly ineffective when asked to take the ball for a second inning. When we look at bullpen performance again (when we have more outings to level things out) we will primarily look at the number of scoreless outings a reliever has in comparison to the number out outings. Now, let’s take a look at the 2026 numbers.

2026 Bullpen Usage

I know what everyone is going to say. “But the lack of good starting pitching has put the Astros in a position to use more multiple inning relievers.” There is no denying that. In back to back games the starters made it through one inning and then one third of an inning. That is brutal and both of those pitchers might have come away with lengthy injuries. There is very little getting around that. The Astros may have the fewest quality starts in the league at this point of the season.

Still, the lab has always been a place where we can take our feelings and throw them into an empirical test. It feels like Espada frequently tries to get one more inning than he should from his relief pitchers. We’ve seen multiple outings where a reliever throws a clean inning or two clean innings, but that next inning is where things go awry. Of course, feelings don’t cash checks around these parts.

What does cash those checks are the actual numbers. Those multiple inning relief outings have been far less successful than they were last season. That is also probably because there have been too many of them and they are going on too long. Some of that can be helped and some of it can’t be. In our commentary on Friday, we talked about the staff stabilizing itself. Simply being able to go out there and throw five or six innings in a start would go a long way to do that.

General managers are made based on what percentage of their decisions that turn out favorably, Managers are made based on how they handle their pitching staff. Yes, decisions of who to sit and when are important. Yet, it is when to pitch certain guys and how long to pitch them that make most of the difference from day to day. The early going has been rough for both guys as both see their contracts run out. The season is long. Hope springs eternal. Throw in your euphemism here. As always, this will be something we track again as the season goes on.