The boycott over police shootings that started in the National Basketball Association has spread across U.S. sports. Teams in Major League Baseball, the WNBA and Major League Soccer joined NBA players in solidarity, prompting a spate of cancellations.

The disruptions pulled professional sports further into the national controversy over police shootings, threatening financial consequences for team owners and players, broadcasters, marketers of memorabilia and even betting houses. The growing protests especially threaten to disrupt efforts by the NBA and MLB to complete their coronavirus-shortened seasons.

Baseball’s Milwaukee Brewers staged a walkout Wednesday over the police shooting of Jacob Blake, a Black man in Kenosha, Wisconsin, joining a boycott by NBA players that began when the Milwaukee Bucks sat out Game Five of their playoff series against the Orlando Magic. The NBA postponed the day’s other matchups.

The Brewers became the first baseball team to join the protests when they decided to not play their home game Wednesday against the Cincinnati Reds. The Seattle Mariners later decided to postpone their game against the San Diego Padres, according to ESPN. The Mariners had 10 Black players on their opening-day roster this season, USA Today reported. That’s more than all of the teams in the American League Central Division, the paper wrote. The San Francisco Giants and Los Angeles Dodgers game was postponed soon after.

WNBA players joined the boycott as well. Atlanta Dream center Elizabeth Williams read a statement on behalf of the league’s players saying the consensus was to not play Wednesday’s games and to “kneel, lock arms and raise fists during the national anthem.”

In Major League Soccer, five matches were canceled in response to the Bucks protest. Players from Inter Miami and Atlanta United stood together in the center of the field to show their support.

Naomi Osaka became the first tennis player to join the boycott. She announced that she wouldn’t play in her semifinal match Friday in the Western & Southern Open in New York, saying, “I don’t expect anything drastic to happen with me not playing, but if I can get a conversation started in a majority-white sport I consider that a step in the right direction.”

The Bucks, owned by hedge fund titans Marc Lasry and Wes Edens, typically play their games about 40 miles (64 kilometers) from Kenosha. Reports swirled earlier this week that teams like the Boston Celtics and Toronto Raptors were considering similar action.

The decision by the Bucks to not play prompted the NBA to cancel Wednesday night’s other playoff games between the Houston Rockets and the Oklahoma City Thunder and the Los Angeles Lakers and Portland Trailblazers.

The boycott had an immediate impact on broadcasters. NBA TV’s coverage turned to a discussion of racial issues in the U.S. Guests like former player Brendan Haywood speculated as to whether players would ultimately leave the bubble, the Orlando site where the playoffs are being held, possibly putting an end to the National Basketball Association’s season.

Kenny Smith, a commentator on the TNT network and a 10-year veteran of the league, walked off the set in solidarity with the players.

“As a Black man, as a former player, I think it’s best for me to support the players and just not be here tonight,” he said.

Shares of DraftKings Inc., an online betting outfit, fell as much as 4.1 per cent in extended trading before paring their decline. Penn National Gaming Inc. was also down as much as 1 per cent.

Lakers superstar LeBron James was among those who tweeted their support for the Bucks. James’s tweet, which included expletives, ended with “We demand change. Sick of it.”

NBA players have scheduled a meeting Wednesday to discuss next steps, according to the Athletic.