BOSTON — When Justin Verlander takes the mound Saturday night for Game 1 of the ALCS, he’ll do so as one of baseball’s most recognizable players: A seven-time All-Star, a former Cy Young and MVP Award winner, a Cy Young candidate again in 2018, and a likely future Hall of Famer.

But the 35-year-old right-hander’s familiarity, first fostered over parts of 13 stellar seasons with the Detroit Tigers, belies the fact he has been a fundamentally different pitcher since joining the Astros on Aug. 31 of last season.

Verlander was still plenty good in his final seasons in Detroit, but — like many pitchers in their mid-30s — his time as a front-of-the-rotation ace seemed coming to an end. After hernia surgery and a rough 2014 season, he rebounded to enjoy strong years in 2015 and 2016, but the velocity on his trademark fastball was down a few ticks, his once-devastating changeup was losing its effectiveness, and at the time of the trade, he was walking more batters than he had in any season since 2008, while he was still a developing pitcher.

Then Verlander joined the championship-bound Astros, and something changed. He was the same guy — the same arm, the same mechanics, the same close-cropped beard — but the numbers suggested the presence of some secret fountain of youth in Minute Maid Park. He showed immediate, drastic improvement in practically every statistical category: His ERA, walk rate, and batting-average against plummeted, his strikeout rate skyrocketed. After going 10-8 with a 3.82 ERA over 28 starts with the Tigers to start 2017, he finished 5-0 with a 1.06 ERA with the Astros. He carried that success into the postseason, then into 2018.

MORE MLB

NIGHTENGALE: Red Sox deal for Sale will pay dividends for years to come

ALCS: Why the Astros have an edge over the the Red Sox

NLCS: Brewers stave off late Dodgers rally to win Game 1

Over his career with Detroit, Verlander sported a 3.49 ERA, a 1.162 WHIP (walks plus hits per innings pitched) and a 3.10 strikeout-to-walk ratio — solid numbers all. In regular-season starts since joining the Astros, he has a 2.32 ERA, a 0.867 WHIP and a 7.93 K:BB rate.

Asked Friday what accounted for the difference, Verlander laughed and said, “I don’t know.” He said he felt he has been more consistent this season than he was in the past, and noted that he took a more proactive approach to making tweaks and adjustments during spring training.

Verlander was a bit more forthcoming in an interview with For The Win in April, suggesting that the Astros’ heralded analytics department offered information that helped.

“When I first got to the organization, they kind of showed me some of the stuff that they can do, and try to do,” he said. “When you get older, every competitive advantage is an advantage, and I wanted that. I joke with guys in the organization that I was probably the first pitcher to come over and ask for more information, because they can kind of give you a lot. I want more. Give me everything you’ve got.”

Verlander is the highest-profile pitcher to show sudden and stunning improvement upon joining the Astros, but he is hardly alone. Before spin rate became something discussed on practically every MLB broadcast, Collin McHugh became its poster boy when, after starting his career 0-8 with an 8.94 ERA, he joined the Houston club in 2014, learned his curveball featured atypically sharp break, and became an effective big-league pitcher.

Charlie Morton has enjoyed the two best seasons of his career since becoming an Astro before the 2017 season. Game 2 starter Gerrit Cole saw his strikeout rate spike and his WHIP drop in his first year with the Astros in 2018. Ryan Pressly was a solid Major League reliever when Houston acquired him before this season’s trade deadline, and an unhittable one thereafter.

Add it all up, and it makes for a historically good pitching staff. The 2018 Astros set Major League Baseball record with 1,687 strikeouts on the season. Their 1.099 WHIP was the lowest of any club since baseball’s dead-ball era ended in 1920. They led the majors in swinging-strike rate, allowed the fewest hits of any club and paced the league in K:BB ratio. Their 3.11 team ERA was the best of any American League team over a full season since 1974.

“Our analytics team, our front office does a great job of providing information, providing thoughts, ideas,” manager A.J. Hinch said Friday when asked about the phenomenon. “(Pitching coach) Brent Strom has been a terrific pioneer of a lot of different things with the pitching department.

“I think credit always starts with the players. Their talent is their talent. Their work ethic, their open-mindedness and their ability to implement is critical in this.”

Strom, who was out of baseball and working at his wife’s Tucson, Arizona, dog-grooming business when Astros GM Jeff Luhnow hired him before the 2014 season, was not available to the media on Friday. In an interview with MLB.com following the Astros’ 2017 championship (https://www.mlb.com/news/luhnows-hiring-of-brent-strom-a-game-changer/c-260820376), Strom deferred credit to Luhnow, saying, “He leaves no rock unturned for information.”

“It's not some thing where they put you in a chamber, press a button, and you come out a better pitcher,” Morton said after the Astros’ workout at Fenway Park. “You're the pitcher that you are with the tools that you have, and they give you suggestions on how to use your stuff a little better.”

In early May, Indians righty and pitch-data firebrand Trevor Bauer created a minor stir when, on Twitter, he responded with a series of thinking-face emojis to an observation about the way Astros pitchers seem to consistently improve spin rates on their four-seam fastballs. Bauer went on to suggest, without saying outright, that the Houston club could be gaining an advantage by using some sticky substance to add more life on fastballs, citing his own research on the effect of pine tar on spin rate. A subsequent study at CrawfishBoxes.com showed that Astros pitchers really do benefit from higher spin rates upon joining the club.

“There's no magic dust,” Morton said. “That's not what happens. I think that's a simplistic way of looking at things, for people to say, ‘Oh, they must be doing something illegal or special.’ Because why aren't they doing it? Well, they haven't caught up yet with figuring out how you look at your hitters and how you look at your stuff, and how those things match up.

“There's not a set philosophy here. I think that buries organizations. The Braves (of the late 90s and early 2000s) — threw down and away, two-seamers down and way, breaking ball, slider. That worked. But hitters have become different; they've become more dynamic, and the objective of the hitters have changed — they've gone from trying to get on base by a walk or a single, to (trying to hit it) to the gaps, or home runs. You can change things and take advantage of that.”

A closer look at the Astros’ pitch usage backs up Morton’s assertion: There’s no obvious, overarching trend, rather a series of individual adjustments that seem to pay immediate dividends. Verlander throws more low fastballs than he did with the Tigers, and has largely scrapped his changeup. Cole throws more high fastballs than he did with the Pirates, and has moved away from his sinker. Roberto Osuna throws fewer sliders. Morton and Pressly throw more curveballs. On and on like that.

Every Major League Baseball team employs an analytics department in 2018, and to some extent, every team is looking at the same type of data the Astros use to try to improve their pitching. Morton noted that his 2016 club, the Phillies, also pointed out the effectiveness of his curveball and steered him toward using it more. But nowhere but Houston does the implementation of that information seem so swiftly and consistently effective.

“I think we do it well,” Morton said. “Everybody has to do their job on a championship team — Top to bottom. As a player in something like this, it's really special. It's a great place to be.”

THE WHY: What makes Astros-Red Sox in the ALCS so exciting?