Every couple of generations, a player comes along who can’t be measured merely by numbers. Since 2014, right fielder George Springer has been that player for the Houston Astros, and his signing of a six-year, $150-million free-agent contract with the Toronto Blue Jays this week suggest the Astros’ days of league pennants and World Series championships may soon be past.

Yet most baseball fans understand that rosters must evolve. Toronto offered Springer the kind of big payday he’d worked for his entire life. The Astros, having locked up José Altuve and Alex Bregman, had long understood they couldn’t keep ’em all, and they did re-sign outfielder Michael Brantley. That said, here’s the part that may be even tougher for Astros fans to swallow: Their team will be less interesting without Springer, the homegrown former number one draft pick whose 2014 debut offered hope of better days to come. Without him, their dugout will be quieter, their clubhouse suddenly missing the teammate who chose the pregame music and narrated the postgame celebrations.

Springer has been so crucial to the Astros that once, when he was on the injured list, then-manager A.J. Hinch requested that Springer remain in the dugout during games because his voice, laughter, and energy uplifted everyone. Presence is one of those intangible qualities that those of us outside the clubhouse may never really understand. Whatever it is, Springer had it, with his high-speed play, power, smile, and connection with the Houston community through charity work.

These last four seasons—the best by far in Astros history—could be summed up in a single image: Springer sprinting toward a ball in the outfield, laying out to scoop it out of the air, then hopping up and heading toward the dugout with an ear-to-ear grin as teammates offered high fives.

He set a tone that made the Astros both wildly entertaining and wildly successful. Astros fans would often ask me, “Are they really having that much fun, and do they really like one another as much as the crazy dugout parties made it appear?” Yes, I’d tell them, they do, and it begins with George Springer. Hinch’s idea to install him at the top of the batting order on May 24, 2016, became the single most important decision he made in five seasons as Houston’s manager.

Springer was an unconventional leadoff hitter in that his game was built around explosive power—and, at times, gobs of strikeouts. But he was perfect in terms of style and substance. His 39 leadoff homers are the eighth-most in major league history, and that was 39 times he gave his club an immediate jolt. He helped turn around the 2016 Astros, who rebounded from a 17–28 start to finish the season 67–50 with Springer at the top of the order. The Astros missed the playoffs that year, but followed up with three straight one-hundred-win seasons and the second-most regular-season victories in MLB between 2017 and 2020.

The Astros won 33 postseason games in this stretch—tied with the Dodgers for the most in the majors—and went to the American League Championship Series four straight years. Last October, a game seven loss to the Tampa Bay Rays left them one game short of a third straight trip to the World Series. (Springer’s 63 postseason games are equal to the number of playoff games that his new team, the Blue Jays, have played in the franchise’s 43-year history.)

Yes, Houston’s 2017 World Series win—Springer was the World Series MVP—will be forever tainted by the sign-stealing scandal that cost Hinch and general manager Jeff Luhnow their jobs and may have contributed to Springer’s decision to play elsewhere. But the Astros continued to win even after getting caught, which makes the whole ordeal and the Astros’ transgressions feel even more pointless and awful.

Springer’s backstory is part of what made him special. His grandfather, George Springer, immigrated to the United States from Panama at nineteen, put himself through college, and wound up leading the Connecticut teachers’ union. He was ultimately summoned to Washington to help a scandal-plagued D.C. teachers union. He once interrupted a lunch with Ted Kennedy to take a call from his son, George Springer Jr., to go over the weekend softball and baseball schedules for George III and his two sisters, both of whom played college softball.

George III grew up with a stutter that he learned to manage through discipline and thanks to his parents’ relentless instilling of self-confidence. It’s still evident at times, and he opted to wear a microphone and be interviewed on national television during the 2017 All-Star Game to set an example for other people who stutter. “I can’t spread a message to kids and adults if I’m not willing to put myself out there,” he said. “I understand I’m going to stutter. I don’t care. It is what it is. It’s not going to stop me from talking and having fun.” He hosted an annual charity event in Houston to raise money and awareness about speech disorders, and in 2014 he was named spokesperson for the nonprofit Stuttering Association for the Young.

“He’s probably the best teammate I’ve ever had,” said former Astros reliever Pat Neshek, who spent the 2015 and 2016 seasons in Houston. “He’s the guy that runs that team. It’s the energy. He’s just so positive in the clubhouse with other guys.”

When Springer struck out four times in game one of the 2017 World Series, reporters asked Hinch so many questions about benching Springer that the manager felt compelled to send his leadoff hitter a string of text messages to check on his confidence. Springer hit .440 with five home runs over the next six games and was named the World Series MVP that year. Likewise, when Springer’s failure to run hard out of the batter’s box could have contributed to a loss in game one of the 2019 World Series, he called Hinch late that night, then met with him the next day. “He just wanted to talk about the play,” Hinch said. “It wasn’t a malicious play where he was disrespecting the game. I think he got caught up in the moment.”

Springer being so bothered about the lone play speaks volumes about why he was so popular both inside and outside the home clubhouse at Minute Maid Park. His production is the kind that isn’t easily replaced, and the Astros say they’ll take a methodical approach to replacing him. But his production is only a fraction of what the Astros are losing in George Springer.