The change can only be described as seismic.

More than two decades of stability at the top of the White Sox’ baseball-operations department came to a shocking end Tuesday evening, when an hour before first pitch, the team announced that both Kenny Williams and Rick Hahn were relieved of their duties as decision-makers.

Williams served as the general manager from 2001 to 2012 before taking over as executive vice president, giving him a nearly 25-year reign atop the department, while Hahn served as the general manager from 2012 to 2023, more than a decade, during which he spearheaded the team’s recent rebuilding effort, which began after the 2016 season.

But it’s the inability of that rebuilding effort to yield a top-of-the-league championship contender that led to this surprising moment, as out-of-nowhere for its timing, coming before the end of the season, as its general occurrence, with the White Sox assumed to be resistant to these kinds of changes.

Frustrated fans, of course, have been begging for a drastic overhaul as Hahn’s rebuilding project sputtered over the last two years. After playoff appearances in 2020 and 2021 that signaled a potential upswing, the team disappointed in spectacular fashion, first with an 81-81 finish in 2022 and now with a record 27 games below .500 with more than a month remaining in the regular season.

Asked about how he felt about his job status earlier this season, Hahn pointed to “the nature of pro sports” on multiple occasions, with teams that fail to meet championship-level expectations typically making these types of changes.

Reinsdorf, who’s been an owner in pro sports for decades, referenced that same line of thinking in the announcement of the changes.

“This is an incredibly difficult decision for me to make because they are both talented individuals with long-term relationships at the White Sox,” Reinsdorf said. “Ken is like a son to me, and I will always consider him a member of my family. I want to personally thank Ken and Rick for all they have done for the Chicago White Sox, winning the 2005 World Series and reaching the postseason multiple times during their tenures. I have nothing but the greatest respect for them as people and appreciate the commitment and passion for the White Sox they exhibited over the years.

“Ultimately, the well-worn cliche that professional sports is results-oriented is correct. While we have enjoyed successes as an organization and were optimistic heading into the competitive window of this rebuild, this year has proven to be very disappointing for us all on many levels. This has led me to the conclusion that the best decision for the organization moving forward is to make a change in our baseball department leadership.”

The White Sox will immediately begin a search for a new department leader, searching for a single voice, according to the team. The anticipation is that someone will be hired by the end of the season.

USA Today’s Bob Nightengale, who just this past weekend reported on “internal interviews” being conducted to determine whether this type of change was necessary, tweeted Tuesday that manager Pedro Grifol is expected to remain in his position moving forward and that Chris Getz, currently the team’s assistant GM and farm director, could be a candidate to lead the department should the team decide to make an internal promotion.

After two years of massive disappointment, whoever wins the job will have a lot to do.

While the farm system has made improvements, gaining recent acclaim for the influx of talent at the trade deadline, it’s not far removed from ranking near the bottom of the sport. But the major league product has been the most troubling for fans, who have watched consistent injuries and underperformance from a core that was expected to power an annual contender.

Grifol was hired by Hahn’s front office last offseason with the task of taking that core and getting it to realize its potential, while also cleaning things up fundamentally and erasing the types of defensive, base-running and plate-discipline mistakes that were so prevalent throughout 2022. Those problems haven’t gone anywhere under Grifol and a new-look coaching staff.

All that will be on the to-do list, along with picking a definite direction for 2024. Hahn said contention was “viable” for the White Sox next season, but there are glaring holes on the roster, particularly when it comes to starting pitching, that would need to be addressed in a significant way to make that the case.

But this is the start many fans were clamoring for. And the kind of change that had been nonexistent on the South Side has finally come to 35th and Shields, where a team that’s made so few playoff appearances over its century-and-a-quarter history will get a new start on making October baseball far more frequent.