HOUSTON — At each of the six American League Championship Series games, from crisp nights in the south Bronx to air-conditioned, indoor comfort on the eastern edge of downtown Houston, a quintet of scouts from the National League champion Washington Nationals quietly settled into their seats at Yankee Stadium or Minute Maid Park and did what scouts have been doing for decades: pointing radar guns at the mound, observing, noting.

Meanwhile, at each of the four games of the NLCS in St. Louis and Washington, the Houston Astros — who would wind up playing that series’ winner in the World Series, which starts Tuesday night — had zero scouts present.

Of all the ways in which the Nationals and Astros are eerily similar — from their orientation around two of the best starting rotations in recent history, to their rosters constructed around homegrown stars, to relentless lineups that were in the top two in their respective leagues in ratio of walks to strikeouts — it is the one fundamental difference between the organizations that makes this World Series so fascinating on a deeper level: the stark philosophical divide between the Astros’ reliance on analytics and the Nationals’ trust in old-fashioned scouting.

It is a story line that can be taken too far, particularly when the divergent philosophies have brought the teams to the same pinnacle of the sport via similar paths of roster construction. Nobody needed much data, or much scouting for that matter, to see that signing Max Scherzer or trading for Justin Verlander was a really good idea. And this much is also true: Analytics vs. scouting is not an either/or proposition for either team.

“We’re sneaky analytical,” ­Nationals General Manager Mike Rizzo said Monday on the eve of Game 1. “And they’re sneaky scouting. We have an eight-person analytics department — that we don’t talk about very much. And they know what they’re doing with scouting. I know — because we’ve tried to make trades with them, and they know our personnel up and down.”

Jeff Luhnow, Rizzo’s Houston counterpart, used the same adjective — “sneaky” — and voiced the same high regard for the Nationals.

“They’re sort of sneaky in what they do,” Luhnow said. “They don’t talk about it a whole lot, but they have good capabilities. We watch their moves. They’re a smart organization, and they’ve got a lot of good people over there. And so do we. We’re sneaky the other way. People label us an analytical organization, but we’ve got really good evaluators, and they use their eyes and their guts. We’re more similar than people think.”

But the fact remains, on any objective list of baseball’s most analytically oriented organization to its least, the Astros and Nationals might just rank first and 30th, respectively. The fascinating part is how those diverging paths have intersected on the sport’s biggest stage, suggesting there is still room for both philosophies in the sport and that in the end it is simply the team that performs best that will win.

“The application of game-planning and [the process of] knowing where you’re going to exploit hitters or where your best weapons are — there’s great knowledge that’s been deployed to these players, more so than ever,” Astros Manager A.J. Hinch said. “[But] once you get out on the field, we want our guys to compete. They’re not analysts out there on the mound.”

At one time, the Astros — who hired Luhnow, a former consultant for McKinsey & Co. who has an MBA from the Kellogg School at Northwestern, in December 2011 — were far and away the most data-driven organization in the game, their methods scrutinized and criticized across the industry.

But thanks largely to their success on the field — a playoff appearance in 2015, a World Series title in 2017, a third consecutive 100-win season in 2019 — the Astros’ gap over the rest of the industry has been reduced in recent years, through the rapid spread of the analytics movement across the game’s front offices, the majority of which are now run by executives with Ivy League degrees and backgrounds in finance and business administration.

That has left the Nationals as the outlier in a sport that has moved away from traditional scouting. The Astros are one of many teams to have fired the vast majority of their scouts — including eight as recently as 2017 — and replaced them largely with data- and video-based analysts.

At the time, Luhnow called the culling of scouts a “reconfiguring,” telling MLB.com the “overall number of people in the scouting department [will] be roughly the same, if not increased.” Other teams have followed the Astros’ model in cutting loose their traditional scouts and replacing them with nontraditional ones, including most recently the Baltimore Orioles, whose GM, Mike Elias, is a former Luhnow lieutenant with the Astros.

Rizzo, a longtime scout who rose through the front-office ranks largely on the basis of his astute talent evaluation, insisted he has no more animosity toward the Astros than he did for the teams the Nationals have already beaten this month — the Milwaukee Brewers, the Los Angeles Dodgers and the Cardinals — just because they have turned away from traditional scouting. But it is also true that others in the scouting fraternity, including some of Rizzo’s guys, would love nothing more than to take down the Astros and, in their minds, win one for the scouts.

And at the very least, the ­Nationals believe their tried-and-true method still works.

“I’m not saying we’re more old-school than [the Astros] are, but I’m saying we trust our guys’ eyes that have seen millions and millions of pitches and at-bats and defensive positionings and outfield arms,” Nationals pitching coach Paul Menhart said. “So we trust these [scouts] and what they tell us. We still have video and data. We use them both. We’re not exclusive with either. And when you have the talent we have on our pitching staff, giving them the right information and not having them overthink it is key.”

During the ALCS, the Nationals had two special assistants, Bob Boone and Ron Rizzi, assigned to the Yankees, and two others, Dan Jennings and Bob Schaefer, assigned to the Astros, with advance scout Jim Cuthbert — whose job all season was to scout the teams the Nationals would play next and file reports in advance of that series — doing his regular work on both teams. Two more video-based advance scouts, who travel with the Nationals, worked behind the scenes. Cuthbert eventually peeled off from the ALCS to meet individually with Aníbal Sánchez, Stephen Strasburg and Patrick Corbin before their starts against the Cardinals. Then he was back in Houston to see the Astros advance against the New York Yankees.

The Astros, by contrast, do almost all of their advance scouting through data and video and, according to a team official, did not employ a traditional, on-site advance scout during the regular season or postseason.

“I don’t really care where [the information] comes from,” said Nationals reliever Daniel Hudson, who has pitched for teams that are heavily oriented toward analytics and teams that are not. “If you can tell me what I should do in a certain situation with a certain pitch against a certain hitter, yeah, obviously I’m going to take all that info and interpret it my own way. And I’m also going to feel my way through a game, not just based on numbers — because if I get beat in a spot where you told me to throw a certain pitch, I’m going to be pissed off.”

The Nationals’ belief in traditional scouting was reaffirmed during the NLCS, after their advance scouts believed they detected patterns in the actions of the Cardinals’ hitters during the division series that made them susceptible to certain pitches in certain situations — information the Nationals’ pitching staff used to limit the Cardinals to six runs, a .130 batting average and a .374 on-base-plus-slugging percentage during a four-game sweep.

On Monday, as the Nationals went through a workout at Minute Maid Park, Jennings and Schaefer, who had scouted the Astros in person for much of the past 10 days, were preparing the reports they would present to the coaching staff later that night and the coaches would then disseminate to the players.

In the other clubhouse, the Astros were doing versions of the same thing, but through different methods and different means. And the only arbiter that will matter, between who was right and who was wrong, would be the scoreboard.

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