Tucson can be thankful the Wildcats didn’t make the Final Four.

With the disturbances that broke out after the University of Arizona’s Sweet 16 and Elite Eight basketball games, who knows what might have happened after an actual national championship game?

That’s one unfortunate lesson from the incidents Saturday night at Main Gate Square: These days, some young fans will take almost any excuse to get rowdy and have a go with police. And the bigger the game, the better the excuse. For Tucson police, the lesson should be that they’ve learned a lot in how to deal with these incidents, but they’ve still got a ways to go.

Unfortunately, they’re likely to have more chances to learn. “Sports riots” have become commonplace on U.S. campuses since we in Tucson first witnessed one back in April 1997, after the Arizona Wildcats won the NCAA basketball championship.

That year, I was reporting on North Fourth Avenue late into the night as action ebbed and flowed around me. I watched, equal parts amused and dismayed, as one neighborhood resident took it upon himself to direct traffic in a gridlocked intersection, dancing happily even as a police line approached and tear gas and bottles criss-crossed over his head.

“In the first year, 1997, we never had any clue what was going to happen,” Tucson Police Chief Roberto Villaseñor told me Tuesday. “We never expected Tucson was going to act this way.”

Ah, innocence.

Since then, these disturbances, also known as “celebratory riots,” have only grown more common, even becoming a subject of academic study by people like Robert Carrothers, an assistant professor of sociology at Ohio Northern University.

“It’s about more than just the sporting event,” Carrothers told me Tuesday. “I think there’s a culture of this, fueled by ESPN and several others. When something happens with your team, you’re supposed to do some kind of extreme celebration. You’re supposed to rush the court. If you don’t go out and flood the streets, you didn’t care enough about the team.”

In some places, sports riots even become part of local tradition among college students and other young adults, he said. Count Tucson as one of those places — Saturday night’s incidents led to 15 arrests and fostered ill will toward police that spread via YouTube, Facebook and Twitter.

But we’re hardly alone in our after-game antics.

The University of Dayton, whose basketball team also lost in the Elite Eight, was home to three disturbances in this NCAA tournament run alone. The first one happened after a first-round win over the school’s rivals from Columbus, Ohio State. Nothing much happened after a second-round victory over Syracuse, then there was a pretty big blow-up after a third-round win over Stanford on March 27. Thousands of students converged on a central block in the student “ghetto” as it’s known, said Maj. Brian Johns of the Dayton police.

“We tried to prevent them from taking the street over,” he said. “We let them go for a little bit, hoping they would party for a while then disperse. Then there was smoke in the crowd (and) we had a report of a roof collapse with unknown injuries.”

The police formed a skirmish line in riot gear and cleared the street, then took a flurry of thrown bottles and even a couple of punches from students, he said. The roof collapse turned out to be minor, but police arrested 27 people in the melee.

Another disturbance after Dayton lost to Florida Saturday was relatively tame by comparison, resulting in no arrests, Johns said.

Here in Tucson, police spent months preparing for this spring’s March Madness in hopes they could stave off the mayhem of 1997 and 2001, when a full-fledged riot occurred, Villaseñor said. Their guiding principle: “The best thing is not to let the crowd build up energy. Don’t let them just hang out in the street and feed on their own frenzy.”

So police mingled with the crowd before and during the game Saturday, then after it ended they urged people to leave. Things went well for a while, but someone set off smoke bombs near the streetcar station on University Boulevard, and the crowd started congregating around it with energy building, Villaseñor said. That’s when the police declared it an “unlawful assembly” and formed skirmish lines in riot gear.

State law describes an unlawful assembly as one where three or more people are gathered with intent to riot. In Arizona, a person riots when “with two or more other persons acting together, such person recklessly uses force or violence or threatens to use force or violence, if such threat is accompanied by immediate power of execution, which disturbs the public peace.”

I’m not convinced the legal threshold was met for declaring an unlawful assembly when police made the call Saturday night. But soon after the declaration occurred and police started to move forward in skirmish lines, the definition was quickly met. People threw bottles and firecrackers at the advancing line.

Whether the police escalated the situation or moved quickly to squelch one that was going to escalate anyway is impossible to know. Some people there, such as Andrew Brown, felt police moved too quickly.

“I was in shock when I first saw it,” said Brown, who went to University after the game because his girlfriend was working there. “It seemed like a really aggressive use of force, the way the whole thing went down.”

Brown was walking just behind a young woman whom a Tucson police sergeant pushed over violently, seemingly without provocation, in a video-recorded incident that seemed to reflect an excessive build-up of aggression on the part of the officer.

Villaseñor said the department is investigating the sergeant’s act but defended the overall approach: “Waiting until damage occurs and people are injured is not the path that we’re going to take.”

That certainly seems reasonable, but there are alternatives, as Madison, Wis., police spokesman Joel DeSpain told me Tuesday. His department has a “special events team” that is present at all big-game crowds and other events. On Saturday night, team members were on Madison’s State Street along with up to 10,000 celebrants after Wisconsin beat Arizona, DeSpain said. Officers monitor surveillance cameras and call in officers the minute they see trouble starting in the crowd.

“Our officers stay in the soft gear,” he said. “They don’t go into the hard (riot) gear unless they have to.”

Maybe that was a key to Madison’s success — amazingly, there were no arrests on State Street Saturday night, though a couple of couches were burned elsewhere in the city. Yes, a wall of police advancing behind black shields can hold the drunken masses at bay, but I can’t help but wonder if crashing the party in battle gear amps up the tension and adrenaline among cops and partyers alike.

Contact columnist Tim Steller at tsteller@azstarnet.com or 807-7789. On Twitter: @senyorreporter