The Big Ten Conference, Southeastern Conference (SEC), American Athletic Conference (AAC), and Big 12 Conference all cancelled their men’s tournaments within minutes of each other late Thursday morning amid growing fears of the COVID-19 coronavirus pandemic.

The Big East tournament, meanwhile, tipped off yesterday. Games continue today at Madison Square Garden.

“The Big Ten Conference will use this time to work with the appropriate medical experts and institutional leadership to determine next steps for moving forward in regard to the COVID-19 pandemic,” said the Big Ten in a statement. “The main priority of the Big Ten Conference continues to be the health, safety and wellness of our student-athletes, coaches, administrators, fans and media.”

The flurry of cancellations come as the NCAA Men’s Division I tournament—March Madness—draws near. Selection Sunday is currently scheduled for March 15.

The NCAA has already announced that spectators will not be allowed into the games, in an effort to slow the spread of the disease. It’s also planning to limit the games to a handful of locations to concentrate safety efforts.

More coronavirus coverage from Fortune:

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—How Europe is adapting to the coronavirus outbreak
—What Xi Jinping’s visit to Wuhan says about China’s coronavirus recovery
—Conferences go online amid coronavirus fears—minus the hallway schmoozing
—Coronavirus may not be all bad for tech. Consider the “stay at home” stocks

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