Over the past 33 years, Georgetown and Syracuse have been one of the most contentious rivalries in college basketball, but as Syracuse prepares to leave the Big East conference for the ACC and Georgetown moves to the Catholic 7 next year, former players, coaches, journalists and alumni recall the history of the rivalry. (Jayne Orenstein/The Washington Post)

The Big East tournament begins Tuesday night with two games featuring only one team that was in the original Big East (Seton Hall) and two teams that will be playing in a different conference next year (Rutgers and South Florida), one of which will be in yet a third league a year after that. College basketball’s most tradition-rich time of year — conference tournaments that pit age-old rivals — begins in earnest at Madison Square Garden with Rutgers-DePaul and Seton Hall-South Florida, matchups we’ll never see again.

Madness, indeed.

There are 30 conference tournaments over this two-week period that began March 6. Only four of those feature the same schools last year, this year and next year. And one of those four, the Big Ten, will add two schools in 2014-15.

The Big East is splitting into two conferences. The ACC is taking on two new members. The year after that, it’ll add two more — unless Notre Dame and Louisville can figure out a way to come aboard sooner.

And relatively, that’s nothing. Conference USA is losing four members — and adding seven. The Western Athletic Conference will stage a 10-team conference tournament beginning Tuesday in Las Vegas. Four of those members are playing in their first WAC tournament — and simultaneously in their last. Six new schools will play in the event next year, when it may or may not be in Vegas, when it may or may not take place on a campus, but when it definitely won’t have any sort of tradition.

“We have kind of a revolving door of members,” said Jeff Hurd, who took over last year as, fittingly, the WAC’s interim commissioner. “It’s very difficult to establish continuity, to find a foothold in any area, when you have members coming and going on an annual basis.”

The focus of the shifts will, this week, be squarely on New York, where the Big East tournament will be toasted and eulogized through the championship game Saturday night. Seven of the current members of the 15-school league will depart in the offseason, taking the name and keeping the right to play the championship at Madison Square Garden, where it has been held since 1983. The tournament could be won by one of those schools: Georgetown is the top seed, and it will lead the so-called “Catholic Seven” into a new world under the Big East banner.

But it also could be won by, say, Syracuse, which will join Pittsburgh in leaving for the ACC this fall. Or it could be won by Louisville, which will also join the ACC, but not until 2014. That’s the same year Rutgers splits for the Big Ten. But next season, Rutgers will be involved in a morphed version of the old Big East — possibly called the “America 12” — that will welcome Central Florida, Houston, Memphis, SMU and Temple.

Got it?

“We’ve lost one of the great college basketball conferences we’ve ever known: the Big East,” said Jay Bilas, who will serve as an analyst of the tournament for ESPN. “It’s done. It’s gone. And there’s sorrow that goes with that.

“And this whole shift, it’s going to keep happening. Nobody’s going to stop this by saying, ‘Hey, a rivalry is going away.’ It’s going to reach its intended conclusion, and that’s to maximize revenue over fewer units.”

“Units,” in this case, means leagues. Which means fans shouldn’t get accustomed to the lineups this year, next or the year after. Connecticut, for instance, has won seven Big East tournament titles, tied with Georgetown for the most in history. The Huskies won’t even be in New York this week, the result of probation because of academic sanctions.

For now, Connecticut is scheduled to join the other Big East schools that play bowl-division football in the to-be-named league. But the Huskies have been examined by both the Big Ten and the ACC — the latter of which will include two of its natural rivals, Syracuse and Boston College. In two years, say, will U-Conn. still be in a conference with Houston and SMU?

“I used to say, and I guess I still say, that nothing surprises me,” Hurd said. “I’m not so sure I can say that anymore.”

The WAC, for instance, has more than 50 years of history — and what feels like as many members over the three-year span from 2011 to 2014. The longest-standing current members are Idaho and New Mexico State. They joined in 2005. And Idaho is leaving after next year.

How are fans supposed to invest time, money and emotion into a conference tournament that no longer includes mainstays such as Nevada and Boise State and next year is scheduled to include Grand Canyon University, Chicago State and the University of Missouri-Kansas City, among others?

“What I’ve found is that it’s only a minority of the fans, sometimes, that are tracking the conference realignment,” said Karl Benson, the WAC commissioner for 18 years until he left in 2012 to run the Sun Belt Conference. “Most fans to some extent, even when it’s over — even when a school leaves the conference — sometimes they have to be reminded.”

Benson spoke Monday morning from Hot Springs, Ark., where the Sun Belt’s men’s and women’s tournaments were to conclude later in the day. And he found himself in the position he has been in before: potentially handing conference championship trophies to schools that are departing the conference, because Middle Tennessee State and Florida International are on their way out.

“The student-athletes are the ones that deserve the postseason,” Benson said. “They had nothing to do with the conference changes, and more often than not, neither did the coaches. So I try to shake hands with both coaches before each game regardless of whether they’re staying or leaving.”

So predicting the results of the tournaments to follow is, in some cases, the easy part. Predicting what schools will participate in which conference tournaments in the years to come? That might prove the more daunting task.