Houston’s Offense Has Hit a Bump in the Road

The St. Louis Cardinals are having a terrible postseason at the plate. They were no-hit for seven and two-third innings by Aníbal Sánchez for goodness sake, and while their subsequent struggles against Max Scherzer and Stephen Strasburg made more sense, it’s fair to say the team has a problem. But St. Louis had the worst non-pitcher wRC+ among teams to qualify for the postseason, so it’s hardly a surprise to see its roster scuffle against playoff rotations.

The Cardinals’ recent three game stretch of futility leaves their team postseason slash line at .207/.264/.331, a truly grim line. No one is questioning their credentials as the worst postseason offense. The next team on the list, though, might surprise you: it’s the Houston Astros, who are hitting a collective .218/.281/.367 through seven games. A dramatic Carlos Correa home run evened their series with the Yankees 1-1, but they’ve still only produced three runs over two games of the ALCS.

Houston’s offensive ineptitude hasn’t yet caught up to them, but it’s still concerning. Heck, the team literally cracked the code in their shelling of Tyler Glasnow in the ALDS, and their offense has struggled mightily even after accounting for that. There’s some chance, however remote, that the Astros’ offense is doomed, that everyone turned into a pumpkin at once. There’s a higher chance that we should just completely ignore this result; during the regular season, the offense produced a 126 wRC+, easily the best in baseball. But rather than take either extreme course, let’s take a closer look at what has happened and see if we can find any takeaways.

One thing you’ll hear ad nauseam at FanGraphs is that context is important when it comes to looking at a team’s season-long stats. Postseason rosters can be constructed quite differently than a team’s regular-season squad, and looking at 162 games of fill-ins and getaway day lineups can obscure a team’s true talent level.

Of course, that doesn’t mean the Astros offense should be worse; in fact, all else being equal, the team’s postseason construction flatters them. Take a look at the percentage of the team’s plate appearances taken by each starter in the regular season and then the postseason:

The Astros have their A-squad on the field pretty much all the time, something that, all else equal, should improve their offense. If you kept everyone’s regular-season batting lines but apportioned playing time in the same ratio Houston has this postseason, the team would have a 142 wRC+ and .379 wOBA, which is patently insane. So playing time isn’t the issue.

Nor is it an issue of the Astros playing over their heads in the regular season before regressing in the playoffs. Take their postseason playing time allocation, but assign each batter their Depth Charts projections rather than their performance in 2019, and the team would project for a .350 wOBA and 122 wRC+ in the playoffs against neutral pitching.

Of course, “against neutral pitching” is a poor assumption when it comes to October baseball. The Astros have faced two teams with lights out bullpens and star-studded rotations, and they haven’t had the luxury of feasting on fifth starters or shuttle squad relievers. Take a look at the pitchers the Astros have faced so far:

That works out to a composite weighted ERA of 3.39 and a wOBA allowed of .277. Their projections would work out to a 3.58 ERA, nearly as good. That’s something like facing Tommy Kahnle every single time you come to bat; it’s a tough environment to hit in.

But even acknowledging the opposition, the Astros hitters have underperformed. When a hitter the quality of the aggregate Astro lineup faces off against a pitcher the quality of their aggregate opponent, odds ratio gives the expected outcome as a .313 wOBA. Instead, they’ve produced a .278 wOBA, which is as bad as it sounds; that was Mallex Smith’s wOBA this year, and he hit .227/.300/.335 in the year of the home run.

As much as hitting like Mallex Smith is terrible, though, it’s not all that unlikely over a small sample. By back-of-the-envelope math, in fact, that outcome is only 1.1 standard deviations below the median outcome, using the rough rule that standard deviation of wOBA works out to .5/sqrt(plate appearances). In other words, the Astros should expect to put up a performance as bad as they have or worse roughly 13.5% of the time.

While we have this metric handy, we can work out how well or poorly each team has hit relative to expectations, given their hitters and the opposition they’ve faced:

These are just approximations: they ignore handedness matchups and home/road adjustments, as well as short rest modifiers for pitchers and pinch-hit penalties for batters. Even so, they paint a good outline of what has happened this postseason. The Rays and Yankees have hit better than expected, while the Astros and Cardinals have disappointed.

Most of that is obvious in the raw batting stats; of course the Yankees have done well after blitzing the Twins, and of course the Cardinals and Astros haven’t looked good. There are lessons to be learned, though. The Rays, for example, had a worse batting line than their overall season statistics, and they overperformed expectations to get there. The Astros pitching staff really is that good. The Twins didn’t hit well, but it wasn’t all down to their own players; the pitchers they faced were excellent, so much so that their projected batting line was no different than that of the Braves despite a far better regular season performance.

When it comes to the Astros offense, there’s only one conclusion to draw: they’ve been disappointing this postseason. Analyzing individual hitters is nearly pointless due to sample size issues, but only Altuve and Bregman have excelled so far, with the rest of the team struggling. Their road won’t get easier from here; the Yankees are going to keep throwing dominant relievers and short-stint starters at the wall to see what sticks, and the two National League teams both boast excellent pitching.

The Astros have a trump card: their own pitching is so good that they can overcome dry spells from the offense. But they could make the playoffs a lot easier for themselves by playing up to their projected level on offense. Even accounting for the imposing opposition they’ve faced, the Astros simply haven’t been up to snuff.