The last major change to the tournament came in 2011, when the field expanded to 68 teams. No expansion is planned for the near future.

PHOENIX (AP) — The NCAA tournament has gone through some massive changes in recent years, the biggest being an expansion to 68 teams.

Don’t expect any more big changes anytime soon.

Though there are annual quibbles about which teams should make the field, the format for one of the biggest spectacles in sports works and the NCAA has no interest in messing with it.

“Over the past many, many decades, the core is really solid, so it’s what can we do to enhance it without taking away from that core,” Mark Hollis, chair of the NCAA’s Division I men’s basketball committee, said Monday.

“Because of the intricacies of the NCAA tournament, I would challenge that’s something you wouldn’t want to touch. We live in a society where we want to change, improve everything, but the core of it is pretty good.”

The NCAA tournament field expanded from 53 to 64 teams in 1985, a format that remained in place until a play-in game was added in 2001 and expanded the bracket to 65 teams.

A big change came in 2011, when the NCAA tournament expanded the field to 68 teams, with the last four to get into the tournament playing in the First Four.

The larger field has helped increase the chances for upsets, which have come fast and furious over the past several seasons.

The audience has expanded with the field; the 2015 NCAA tournament was the most-watched in 22 years, averaging 11.3 million viewers.

“Is it (expansion) possible in the future? Sure, anything’s possible, but I don’t see that in the short term,” said Dan Gavitt, NCAA vice president of men’s basketball championships. “The core of it and the thing that makes it so incredibly popular is what’s protected by this committee, so by and large the traditions that make March Madness the way it is will stay.”

The NCAA has discussed moving the First Four from Dayton, Ohio, or at least expanding it to two sites, but has had a hard time justifying it.

Since becoming the First Four site in 2011, Dayton has been a perfect host. The teams are selected on Sunday and the games are Tuesday night, but the city is always ready and the games usually sell out despite the short turnaround.

Playing games at a second site would make it easier for teams in the West travel-wise, but it may come under the category of why fix what’s not broken.

“That’s the X factor: If we you move it, consider another location, can they deliver that incredible college basketball feel and experience?” Gavitt said. “It’s a risk because you don’t know. Some of the other places where we have first and second rounds somewhat depend on what teams are playing there. That’s always going to be the trick when it comes to First Four.”

The NCAA is looking at changes to the regional rounds of the NCAA tournament.

The tournament’s first weekend is exciting, the games spread across the country and upsets coming at every turn. The Final Four has its own vibe with a national championship on the line and so many other activities surrounding the games.

The regional rounds determine which teams will play in the Final Four, but often don’t get the hype of the tournament’s first and third weekends.

To enhance the regionals, the NCAA is looking at making those games more of a stand-alone event like the Final Four by adding concerts and fan experiences to go along with the games.

“It’ll never approach the size and scope of the Final Four, but for those fans, those four teams in those three days are arguably as good as the Final Four the following weekend, depending on who the teams are,” Gavitt said. “So to make it a bigger and more exciting event for that locality would make it special.”