Rick Pitino will soon be leading his Louisville men’s basketball team in the ACC. (Ed Reinke/AP)

In 2005, the athletic programs at the University of Louisville enthusiastically joined the Big East, a move Tom Jurich, the Cardinals’ athletic director, said came about because “the stability of that conference really matched up to what were looking for.”

Wednesday, Louisville announced it would depart for the Atlantic Coast Conference, the latest indication that — in the landscape of college athletics, which seems to shift daily — there is precious little stability remaining in the Big East.

“When it began to deteriorate, we felt that all our options were pulled away from us,” Jurich said in a conference call with reporters. “We had to look. We were forced to look.”

The ACC’s school presidents voted unanimously Wednesday morning to admit Louisville, providing the conference with a swift response to the departure of one of its founding members, the University of Maryland, which announced last week that it will leave for the Big Ten.

“The addition of Louisville, with its aggressive approach to excel in every respect, will only strengthen our conference,” ACC Commissioner John Swofford said on the conference call. “Louisville is committed in its approach to doing everything at the highest level, and as we’ve seen, especially in recent years, their success has been well documented and their facilities are truly outstanding.”

The ACC effectively chose Louisville over the University of Connecticut, according to an ACC source, at least in part because of recent turmoil in the Huskies’ basketball program, which put off some of the conference’s presidents and chancellors. The Cardinals football team, now 9-2, would gain a Bowl Championship Series bid with a win Thursday night against Rutgers. The men’s basketball team has a storied past that includes two national championships and two Final Four appearances in the last eight seasons. The Cardinals are currently ranked fifth in the nation.

Louisville’s departure is only the latest blow to the Big East. In just more than two months, the ACC has pilfered four Big East schools: Syracuse, Pittsburgh and Notre Dame (though the latter not for football), and now Louisville. Go back nearly a decade — to 2003 and 2004, when the ACC swiped Miami, Virginia Tech and Boston College — and no league has raided another more frequently or thoroughly than the ACC has the Big East.

Louisville’s move prompted Big East Commissioner Mike Aresco’s second farewell speech in nine days, following Rutgers’s confirmation Nov. 20 that it was leaving for the Big Ten. Louisville becomes the seventh Big East member in the past year to announce that it’s leaving, following West Virginia, Texas Christian (which reneged before even suiting up as a Big East school), Pittsburgh, Syracuse, Notre Dame and Rutgers.

“The Big East has anticipated the continuing realignment that is reshaping college athletics and has already made important additions as part of our vision for the future,” Aresco said in a statement. “We will continue moving forward to fulfill that vision, which includes a strong national football conference and a strong and storied basketball conference. . . . We are committed to a vibrant and dynamic future for the Big East Conference.”

Yet what that future holds is unclear. Neither Georgetown Athletic Director Lee Reed nor Coach John Thompson III could be reached to comment Tuesday. An athletic department spokesman said Georgetown was referring all questions about the matter to the Big East office. Other schools scheduled to join the Big East — which admitted Tulane and East Carolina this week, and is also scheduled to add six other programs in 2013 — are wondering what will happen next.

“I’m nervous,” said Navy football Coach Ken Niumatalolo, whose program is slated to join the conference in 2015. “When we made this decision to go into the Big East, I think we still weren’t really sure.”

The timing of Louisville’s move is unclear. Big East bylaws stipulate that a school must pay a $10 million exit fee and give 27 months’ notice before departing, but other schools have agreed to pay a higher fee for the right to leave sooner. Maryland will begin play in the Big Ten in 2014-15, so Louisville’s arrival into the ACC makes sense then.

Swofford, whose conference began the seismic shifts in college athletics with its initial moves in 2003, said the ACC is “very, very comfortable at 14” members, and that he doesn’t see further expansion in the near future. The ACC replaced Maryland just nine days after the Terrapins announced their departure, but Swofford said the swift addition of Louisville won’t affect the conference’s pursuit of a $52 million exit fee it feels Maryland owes.

“I don’t think those two things are connected,” Swofford said. On Monday, the ACC filed suit against Maryland in an attempt to ensure the payment.

Gene Wang, in Philadelphia, and Alex Prewitt contributed to this report.