NFL side the Baltimore Ravens say the United States must tackle racism “head-on” and have promised to use their platform to “drive change now”.
In a powerful statement on social media, the Ravens called for those responsible for the shooting of Jacob Blake to be brought to justice.
Blake, a black man, was shot and injured by police on Sunday in Wisconsin, near Milwaukee.
“This is bigger than sports,” the Ravens statement said.
“Racism is embedded in the fabric of our nation’s foundation and is a blemish on our country’s history.”
The statement also highlighted the killing of Breonna Taylor, an African-American woman shot during a drugs investigation in March.
Several NFL sides cancelled practice on Thursday, while sports across the US boycotted matches in protest at Blake’s shooting.
“It is imperative that all people – regardless of race, religion, creed or belief – come together to say: ‘Enough is enough,'” the statement continued.
“It is time to accept accountability and acknowledge the ramifications of slavery and racial injustice.”
Meanwhile, seven MLB matches were called off on Thursday, and there was a poignant protest at the New York Mets v Miami Marlins game.
Both sets of players took the field in silence for 42 seconds – the number of Jackie Robinson, the first African-American to play in the league – before walking off.
A Marlins player also left a Black Lives Matter T-shirt on home plate.
The NBA has held talks to discuss when to resume matches after the play-offs were postponed on Wednesday and Thursday.
NBA executive vice-president Mike Bass said the league was “hopeful to resume games either Friday or Saturday”.
The WNBA also postponed Thursday’s games, having done the same a day earlier.
In the MLS, an investigation into the potential use of racist comments by Real Salt Lake owner Dell Loy Hansen has been launched by the league.
In the report by The Athletic, the club’s former head scout Andy Williams recounts incidents of racist comments allegedly made by Hansen.
“We are deeply concerned about the allegations made in a report published this evening concerning language used by and the conduct of Real Salt Lake owner Dell Loy Hansen,” MLS said in a statement.
“Major League Soccer has zero tolerance for this type of language or conduct and will immediately commence an investigation.”
The NHL announced that four games scheduled for Thursday and Friday had been called off.