Last night, behind seven brilliant innings of work from Masahiro Tanaka, the Yankees blanked the Astros 5-0 to take a 3-2 lead in the ALCS. After that shutout, Houson has now scored just nine runs in the first five games of this series, and they are hitting an anemic .147/.234/.213 so far in the ALCS. This isn’t what anyone expected from a club that produced baseball’s best batting line in the regular season and then thoroughly pummeled Red Sox pitching in the first round of the postseason.

So, how has a team that scored nearly 900 runs in the regular season gotten so thoroughly shut down against the Yankees?

Obviously, a lot of credit has to go to the Yankees pitchers, particularly their starters. So much has been made of the advantage the Yankees have when their relievers come into the game, but the Yankee rotation has been the dominant force so far, holding the Astros to a .404 OPS during their 28 innings of work. It’s always harder to score runs in October, and this Yankee pitching staff is particularly good, so we shouldn’t be too surprised that the Astros have found it hard to score runs off some of the best arms in baseball.

But just crediting the opponent isn’t really an explanation for how a team that put up runs all year long is unable to sustain rallies now. So let’s look at a few key points that have driven the Astros’ offensive struggles in this series.

Hard-Hit Balls Finding Gloves

While no one like to use the term “bad luck” for a struggling offense since it feels like an excuse, the reality is that Astros hitters aren’t struggling as much as their offensive numbers would have you believe. Unfortunately for them, they just haven’t gotten anything out of the balls they’ve hit well yet.

Using Statcast data, MLB classifies batted balls in six quality-of-contact buckets, with “barrels” representing the balls that fall into the exit-velocity/launch-angle windows that lead to the most offensive success. So far this postseason, there have been 86 barreled balls. Of those 86, 69 of have gone for hits, good for an .802 batting average. Batters have slugged 2.779 on those types of batted balls.

In the ALCS, the Astros have barreled six balls over the first five games. Here are the results of those well-struck balls.

Astros Barrels in ALCS Game Batter Pitcher Result Exit Velocity Distance 1 Jose Altuve Masahiro Tanaka Line Out to CF 98 378 1 Alex Bregman Masahiro Tanaka Line Out to CF 104 397 1 George Springer Masahiro Tanaka Fly Out to CF 102 396 3 Yulieski Gurriel CC Sabathia Fly Out to CF 101 367 3 Carlos Correa Adam Warren Fly Out to CF 104 396 3 Yulieski Gurriel Adam Warren Line Out to CF 106 384

No, that’s not a copy-and-paste error in the results column. The Astros have hit six barreled balls in this series, and all six of them have been caught in deep center field by Aaron Hicks. Here’s what the spray chart looks like.

These balls have all been scorched, but in every case, they were just hit to the wrong part of the ballpark and hung up just long enough for Hicks to make a play, leaving the Astros with nothing to show for their solid contact.

In the ALDS, the Astros hit 10 balls classified as barrels. On those 10 batted balls, they went 10 for 10 with a single, two doubles, and seven home runs. In the ALDS, their wOBA on barreled balls was 1.740; in the ALCS, it’s .000. Maybe the Yankees deserve some credit for positioning Hicks particularly well in this series, but mostly, this is just bad luck. The average hit probability Statcast assigned to these six balls was 71%, so we’d have expected the Astros to get something like four or five hits, mostly doubles and homers. Instead, they’ve lined into six very well struck outs.

And the numbers show that, despite having now been outscored 21-9 by New York, the Houston offense has actually been mostly comparable to New York’s. Consider: over the first five games, the Yankees have produced 42 batted balls classified by Statcast as either a Barrel, Solid Contact, or Flare/Burner. Again, these categories denote the sort of contact that most often leads to hits. By comparison, the Astros have recorded 37 examples of such contact, or just one fewer per game. The bad luck is also expressed in the “expected” offensive numbers. The Yankees have produced an .816 xwOBA; the Astros, a .718 xwOBA. So, advantage New York. But the actual wOBA figures, .771 to .509 in New York’s favor, once again reveal a striking imbalance.

Right-Handed Heaviness

Because the Astros’ best hitters are all right-handed, they had the sixth-most RHB-vs-RHP plate appearances in the majors this year. It wasn’t a problem, though: their righties put up a 128 wRC+ against opposing righties, by far the best mark in the big leagues.

In the postseason, though, it’s easier to play match-up games, and since most of the Yankees best pitchers are righties, 81% of the Astros’ plate appearances in the ALCS have come against right-handed pitching. In the division series against Boston, only 49% of their plate appearances came against right-handers, since the Red Sox’ best arms are predominantly southpaws. We shouldn’t be terribly surprised that a lineup composed mostly of good right-handers beat up on a team that threw a bunch of lefties, nor should we be surprised that the same offense is now having more problems against a team with lots of really good righties.

The good news for the Astros is that, if Justin Verlander can win them Game 6, they’ll be drawing the left-handed CC Sabathia in Game 7, and you can imagine they’ll get plenty of Aroldis Chapman in that game, as well. If the Astros can get to a winner-take-all finale, the platoon advantage will move to their favor. As good as Sabathia has been for New York in the postseason thus far, he’s the kind of pitcher against which the Astros lineup can get healthy in a hurry.

Regression to the Mean

Certainly, the Astros weren’t due for some kind of absurd slump like this to offset how well their offense had played this year, so let’s not get into a gambler’s fallacy and say that they had this kind of struggle coming. But when quoting the team’s regular-season offensive numbers as a reason why these struggles are so surprising, we should also acknowledge that the Astros’ results this year were also better than they had any real right to expect.

Just like we noted that the Astros have gotten unlucky on hard-hit balls in this series, their results on contact were probably the most fortunate in baseball during the regular season. By Statcast’s xwOBA calculation, the Astros hit balls that should have resulted in a .330 wOBA, but they actually posted a .355 wOBA; that 25-point difference is the second-largest in baseball, behind only the Rockies, who play in the ballpark that does the most to inflate batted-ball value. This isn’t a Minute Maid Park effect either; in 2016, the Astros posted a wOBA four points lower than their xwOBA.

Among hitters with at least 250 plate appearances this year, Marwin Gonzalez had the second-largest gap between his wOBA and xwOBA. Jose Altuve was sixth, though certainly some of that gap is attributable to his speed. Josh Reddick (.330 xwOBA), Yulieski Gurriel (.327), and Alex Bregman (.338) combined to give the lineup valuable depth production, but probably aren’t quite as good offensively as their 2017 numbers make them look.

The Astros offense is definitely one of the best in baseball, but based on their quality of contact this year, they were more in the same tier as the Yankees, Dodgers, and Indians, rather than being on a level all their own. And the Yankees just throttled Cleveland’s hitters to an even more extreme degree in the division series, limiting them to a .250 wOBA in the first round.

Which brings us back to crediting the Yankee pitchers. Faced with probably the toughest pair of lineups any team has faced in the first two rounds of the playoffs, the Yankee pitchers have just taken over, which is why New York is one win from the World Series. They’ve certainly gotten some balls to go their way in this series, and I wouldn’t rule the Astros hitters out just yet, but instead of asking what’s wrong with Houston’s offense, the story should probably still be the dominance of this Yankee pitching staff.

The Astros now have two games left to write a different ending.