NFL commissioner Roger Goodell admitted Friday the league had been wrong to silence player protests as it responded to calls from a group of players to issue an explicit condemnation of racism.
In a video message posted on social media, Goodell said the league would now support peaceful protests from players in future.
Goodell's message came as a wave of protests against police brutality and racism continued across the United States following the death of unarmed black man George Floyd in Minneapolis on May 25.
"It has been a difficult time for our country," Goodell said. "In particular, black people in our country."
"We, the National Football League, condemn racism and the systematic oppression of black people.
"We, the National Football League, admit we were wrong for not listening to NFL players earlier and encourage all to speak out and peacefully protest.
"We, the NFL, believe Black Lives Matter."
The NFL had been criticized for a statement released last Saturday which failed to directly reference racism or police brutality.
On Thursday, a group of several prominent NFL players including Super Bowl-winning quarterback Patrick Mahomes and Odell Beckham Jr released a video demanding that the NFL condemn racism and support protest.
"How many times do we need to ask you to listen to your players?" Kansas City chiefs ace Tyrann Mathieu asked in the video.
"What will it take?" Arizona's DeAndre Hopkins added.
"For one of us to be murdered by police brutality?" Cleveland's Jarvis Landry asked.
'I PROTEST WITH YOU'
Goodell, who has faced criticism in the past for his handling of NFL player protests launched by Colin Kaepernick in 2016, insisted he would now be a sympathetic ally for players.
"I personally protest with you and want to be part of the much needed change in this country," Goodell said.
"Without black players, there would be no National Football League.
"We are listening, I am listening and I will be reaching out to players who have raised their voices and others on how we can improve and go forward for a better and more united NFL family."
Green Bay Packers player Aaron Jones said he is pleased that Goodell has changed his outlook.
"I am just glad he is listening. He has corrected himself and he has open ears," Jones said.
The NFL, which is the most popular professional league in the United States, has long struggled with allegations of racism.
Many team owners are supporters of US President Donald Trump, who led stinging criticism of player protests in 2017, plunging the league into a protracted crisis.
Trump had said players like former San Francisco 49ers quarterback Kaepernick who kneeled during the national anthem were "sons of bitches" who should be fired.
At the time, Goodell had effectively sided with Trump, saying he believed players should stand for the national anthem.
Kaepernick, who launched his "take a knee" protests in 2016 following the deaths of several unarmed black men during confrontations with police, was released by the 49ers in 2017, four years after taking the team to the Super Bowl.
Since then, Kaepernick has remained unemployed, with no team willing to sign him, even as a back-up. Kaepernick later sued the NFL, alleging he had been blacklisted by team owners for his political beliefs. The case was settled in 2019.
Kaepernick's protest has continued to reverberate, however, with many involved in this week's protests, as well as some police officers, this week dropping to one knee in solidarity with the cause.
However Trump on Friday waded back into the NFL culture war, writing on Twitter that he believed players should stand for the national anthem.
"OLD GLORY is to be revered, cherished, and flown high," Trump wrote. "We should be standing up straight and tall, ideally with a salute, or a hand on heart.
"There are other things you can protest, but not our Great American Flag - NO KNEELING!"
Trump had been responding to a controversy which erupted earlier this week when New Orleans quarterback Drew Brees suggested players who knelt were "disrespecting" the flag.
Brees subsequently apologised -- drawing criticism from Trump.