In The Lab: What Does BPO Say About Our Hitting Coaches?

One of the benefits of waiting until late May to look at statistics is that individual games have less of a difference on overall numbers. In April, it looked like the Astros hitting coaches were the toast of the town. The team was leading the American League in runs scoring. They were taking more pitches. They were taking more walks. It felt like there was a new message being delivered to hitters and they were listening. Of course, not we have gone most of the way through May (May 19th as of these numbers) and those gains may have slowed.

We have been looking at bases per out now for a couple of different articles. We looked at the catchers and we will look at the infield and outfield eventually, but this time we are looking at the offense as a whole. For comparisons sake, we will take a look at the 2025 numbers since those numbers were probably the numbers that got the past two hitting coaches sent out of town.

Now that the offense has seemingly come back to earth it bears asking whether there were any meaningful and lasting changes in the Astros offense. With one very notable exception, the players are basically the same. That exception is Yordan Alvarez as he spent most of 2025 on the shelf and wasn’t himself for most of the time when he was healthy. Is that enough to explain the difference?

Keep in mind that we will add BPO+ for reference sake. In case you missed our primer article, the major league BPO in 2025 was .670. The BPO so far this season is .663, Last year Daikan Park was perfectly neutral while this year it is playing one percent above average. Given that information let’s see if we have seen in real gains from 2025 to 2026.

That’s not an insignificant improvement. Of course, those gains might be short-lived as the Astros will live without Jose Altuve for a month and Carlos Correa for the remainder of the season. That doesn’t even mention any parts and pieces that will be bartered off before the August 3rd trade deadline. However, if we assume that forces will remain constant (never a good assumption) then we can note where the gains have occurred.

If we note where the gains have occurred then we can possibly isolate those gains down to either hitting talent or hitting approach. Keep in mind that the BPO formula is made up of four components. Total bases is obviously the biggest driver and one probably more dependent on hitting talent. The smaller components are walks, hit by pitches, and stolen bases. Walks are the main component tied to hitting approach.

Before we dive into the numbers, we have to acknowledge the impact of usage. This is why we will break down the infield and outfield in subsequent labs. Those numbers tell us who should play and how often they should play. Naturally, some of that is dependent on availability, but some of that is in the hands of the manager. A statistic like BPO can tell us more about damage than traditional numbers like batting average or more crude sabermetrics like OPS.

The Astros are 49 games into the season, so we will not look at the totals for these four components. Instead we will look at the per game averages to see where if any growth we see in the numbers. 30 BPO points is pretty significant, but as you will see the per game totals might be more subtle. It shows you how small tweaks can have a pretty significant impact on the numbers.

Seeing the numbers expressed this way also helps us understand the relative impact of each metric. The best team in baseball history in steals may have averaged 1.50 steals per game. So, an extra base per game is all you would get out of that exchange. However, as you can see, the 2026 is walking nearly 0.6 times more per game than the 2025 outfit. The impact of hit by pitches is also negligible.

So, the bulk of the difference will come from total bases and walks. The combined additions there equal almost one more base per game. That is the difference between a below average offense and an above average offense. Two total bases would probably take you from below average to elite. So, we aren’t really talking about huge differences this year.

The question then comes down to how we explain the improvement. It is an overall hitting approach improvement or are we talking isolated improvements in personnel. So far, Alvarez has not missed a game and has hit like expected, It turns out that 2025 might be the anomaly there. Otherwise, it looks like Christian Walker is the only significant hitter to show considerable improvement from 2025 to 2026. Can that be attributed to the hitting coaches? I suppose anything is possible.

it should be noted that Jake Meyers and Jeremy Pena have done very little and they were solid and very good respectively last season. There is still a ton of time for them to look more like they looked last year and that could further boost the numbers we are seeing. A more productive Yainer Diaz could also give a little boost to the lineup. Nothing is ever fixed in the middle of a season. So, given these numbers do you lean more on the hitting coaches being the reason for improvement or is it because of individual performances?