ST. PETERSBURG -- A picture hanging in the Astros’ offices at Union Station adjacent to Minute Maid Park -- taken just before Game 1 of the 2017 World Series -- shows the team lined up neatly along the baseline. The names on the backs of the jerseys are familiar ones, though five years later, very few remain in a Houston uniform.

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The challenges of keeping the core of a championship team together are difficult, and the Astros have seen their share of high-profile players leave for greener pastures and more money. George Springer, the 2017 World Series Most Valuable Player, and playoff hero Carlos Correa left after the ‘20 and ‘21 seasons, respectively, breaking up Houston’s homegrown core that included Alex Bregman and Jose Altuve.

Beyond that, the Astros lost Charlie Morton and Dallas Keuchel to free agency in the years following their championship and haven’t skipped a beat. Houston clinched its fifth American League West title in six years with a 4-0 win over the Rays on Monday, and at 97-51, it has a chance to tie 2019’s club record for wins at 107. And one of the key performers from that club -- Gerrit Cole – left after the World Series loss to join the Yankees.

So how do the Astros keep winning, keep dominating the division despite losing so many key players years after year?

“It starts with scouting, drafting and development,” Astros general manager James Click said. “We can’t continue -- and no team can continue -- to have success at the Major League level unless you're constantly bringing talent up from the Minor Leagues. Our player development group and our scouting group have done a tremendous job continuing to provide us with young players who can step in. We've been fortunate that we've had young players step into the roles that we've needed.”

Only Bregman, Altuve, Yuli Gurriel, Justin Verlander and Lance McCullers Jr. remain from the 2017 World Series championship club. New faces like sluggers Kyle Tucker (taken with the No. 5 overall pick in the 2015 Draft) and Yordan Alvarez (acquired from the Dodgers in a lopsided trade in 2016) have stepped in to fill key roles, along with rookie shortstop Jeremy Pena. Top pitching prospect Hunter Brown figures to play a role in the postseason.

“That says a bunch about the culture that’s built here over the last decade,” said designated hitter Trey Mancini, who was acquired from the Orioles in an Aug. 1 trade. “That’s the answer to why so many great players have left here and even as they move on to other teams, other guys come in and step up.”

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There is no better example of the Astros’ success at developing players than their starting rotation. Houston currently has a six-man rotation, including five homegrown arms: McCullers, Framber Valdez, Cristian Javier, José Urquidy and Luis Garcia. Verlander is the exception.

“I think that our pitching development group deserves special applause for what they've been able to do to develop players, not even just in the Minor Leagues, but to continue to develop them at the Major League level,” Click said.

McCullers (taken No. 41 overall in 2012) was a high Draft pick, but Valdez, Javier, Urquidy and Garcia were unheralded international signings. Valdez blossomed into an All-Star and should finish high in the AL Cy Young voting, while Javier entered Tuesday ranked second in the AL with 11.83 strikeouts per nine innings. Urquidy and Garcia have a combined 25 wins.

“We have to be able to find talent anywhere in the Draft, internationally, anywhere we can find it, even independent leagues,” Click said. “But scouting is half the equation, and development is the other. And I want to make sure that we recognize both, because scouting those guys and having our starting rotation largely coming from the international scouting department is a huge credit to them. But at the same time, these are players who were developed by our coaches, many of whom are with the big league team.”

The Astros have avoided giving out massive long-term deals, which is why they didn’t re-sign Springer, Correa and Cole. Instead, they’ve tried to spend more wisely, giving extensions to Bregman, Altuve, Alvarez and closer Ryan Pressly before they hit free agency. They’ll likely try to lock up Tucker and Valdez soon, too.

“As much as we hate to see those faces of the franchise ultimately leave, we have to make sure that we have succession planning, and having player development allows us to do that,” Click said. “We're always going to maximize our spending, our investment on this team … and that's always going to depend on the talent that we have coming up through the pipeline.”