PHILADELPHIA -- Scheduled national anthem singer Sevyn Streeter said she was told by the 76ers she could not perform on Wednesday night because of her "We Matter" jersey.
She was slated to sing before the 76ers' season opener against the Oklahoma City Thunder, but she said in an interview with The Associated Press late Wednesday that she was told she would not sing just minutes before her performance.
"I'd say two minutes before we were about to walk out ... the organization told me that I could not wear my shirt while singing the national anthem at their game,'' the R&B singer said by phone. "I was never given any kind of dress code. I was never asked beforehand to show my wardrobe."
A source told ESPN that any on-court performer -- singer, dancer, entertainer -- must sign a contract that gives the 76ers the right to cancel a performance if the standards described in the contract are not met. The Sixers declined to say why Streeter's performance was canceled, but according to a report by CBS Philly, the contract prohibited political statements. The 76ers offered her an alternate shirt and song, but she refused, the report said.
"The Philadelphia 76ers organization encourages meaningful actions to drive social change. We use our games to bring people together, to build trust and to strengthen our communities. As we move from symbolic gestures to action, we will continue to leverage our platform to positively impact our community," the Sixers said in a statement.
A team representative met with 76ers players Thursday to explain what happened, and multiple players came away from the meeting upset by what they were told, a source told ESPN's Jeff Goodman.
The players met at their practice facility Thursday in Camden, New Jersey, and are considering whether to respond to Streeter's cancellation.
"Everybody expressed their emotions about it," forward Robert Covington said. "We want to take steps about it. We just don't know exactly what steps we want to take. We talked about a lot of different things."
The Sixers play at home Saturday afternoon against Atlanta.
Sixers guard Gerald Henderson said he thought something seemed different moments before the anthem, which was performed by Jemila Worley, a Sixers dance team member.
"I saw the little pause there. ... I was wondering, something had crossed my mind like, 'What's going on? Did something happen?'" Henderson said. "That was pretty big time for a cheerleader to step in there, and she killed it!"
Henderson did not know that Streeter was supposed to sing the anthem until told after the game by a reporter.
"There's a lot going on, man," Henderson said. "People care about these things that are happening, as well as they should. And they are going to express themselves in different ways. ... People are trying to make statements, I guess."
The NBA had no comment.
Streeter has written songs for Chris Brown, Ariana Grande and other stars. In 2013, she had a Top 40 hit with "It Won't Stop," a duet with Brown that reached Recording Industry Association of America gold status.
The singer, born Amber Denise Streeter, said she was very hurt by the NBA team's actions.
"I was angry, extremely, extremely angry, and disappointed and honestly brought to tears by all of it. It broke my heart,'' she said. "Honestly, I was very excited about being able to perform the national anthem. I was really looking forward to that."
This isn't the first time the Sixers were dragged into a recent national anthem controversy. A woman performing the national anthem before their NBA preseason game in Miami did so while kneeling at midcourt.
Denasia Lawrence opened her jacket just before she started to sing, revealing a "Black Lives Matter" shirt, then dropped to her left knee and performed the song. She said it was her way of protesting racial oppression.
The anthem issue has been a major topic in the sports world in recent months, starting with the decision by San Francisco 49ers quarterback Colin Kaepernick to not stand while it is played. Kaepernick cited racial injustice and police brutality among the reasons for his protest, and athletes from many sports -- and many levels, from youth all the way to professional -- have followed his lead in various ways.
"I also felt it was important to express the ongoing challenges and ongoing injustice we face as a black community within the United States of America -- that's very important to me," Streeter said. "Yes, we live in the greatest country in the world, but there are issues that we cannot ignore. This can't be ignored."
ESPN staff writer Ohm Youngmisuk and The Associated Press contributed to this report.