(CNN) -- Pressure is mounting on a National Basketball Association team owner who allegedly made racist comments.
A litany of NBA legends have slammed Los Angeles Clippers owner Donald Sterling. Former players like Michael Jordan, Kareem Abdul-Jabbar, Magic Johnson and current greats such as LeBron James have said that if Sterling did indeed say what recordings posted on two popular news sites seem to suggest, he must face consequences.
Kevin Johnson, a former NBA player who is the mayor of Sacramento, California, called for an "immediate investigation" in a statement on the National Basketball Players Association website.
If the reports are true "there needs to be strong and swift action taken," he said.
Johnson spoke on CNN's "New Day" on Monday, saying that Sterling is in a unique position and any measures taken should consider that.
"When you have an owner, they're in a position of influence," he said. "And players are out there working very hard to be good at their craft, to win ballgames, but every time we have a playoff game, there's dollars to be made. And if those dollars go into the pocket of an owner who doesn't value or respect players, that is very problematic."
On Saturday, TMZ posted a 10-minute recording of a phone conversation, allegedly between Sterling and his girlfriend V. Stiviano. According to the website, Sterling reportedly made discriminatory remarks during an argument he had with her on April 9.
The man alleged to be Sterling seems mad about a photo the woman posted to Instagram with Magic Johnson.
"In your lousy f**ing Instagrams, you don't have to have yourself with -- walking with black people," the man says.
"If it's white people, it's OK?" she responds. "If it was Larry Bird, would it make a difference?"
Bird, the longtime Boston Celtics star, was Johnson's NBA rival.
"I've known (Magic) well, and he should be admired. ... I'm just saying that it's too bad you can't admire him privately," the man on the recording says. "Admire him, bring him here, feed him, f**k him, but don't put (Magic) on an Instagram for the world to have to see so they have to call me. And don't bring him to my games."
On Sunday, the sports website Deadspin released a 15-minute audio recording of a conversation that purports to be Sterling talking with Stiviano earlier this month about her Instagram photo feed.
If authentic, the remarks seem to reflect Sterling's embarrassment and frustration with Stiviano over her associating with African-Americans at Clippers games and for posting such pictures on her Instagram account.
Neither website has said how it obtained the recordings. Stiviano's lawyer's office said Sunday that she didn't release the recordings but that they are legitimate.
"This office understands that the currently released audio tape of approximately 15 minutes is a portion of approximately one (1) hour of overall audio recording of Mr. Donald T. Sterling and Ms. Stiviano, and is in fact legitimate," Mac E. Nehoray said in a news release. "Ms. Stiviano did not release the tape(s) to any news media."
The NBA has demanded Sterling be barred from all playoff games this season. The players also want an accounting of past accusations of racism against Sterling; an explanation of what kind of discipline might be issued; assurance that the league commissioner will work with the association; and a promise that the investigation will be conducted swiftly.
Player protest and outrage
On Sunday, NBA players made it clear how they feel about the controversy.
As the Clippers warmed up for an NBA playoff game, the players removed their warmup shirts bearing team logos to reveal red T-shirts worn inside out, with the logos hidden. They finished warming up, removed the red shirts and played the game wearing their regular uniforms.
Sterling wasn't at the game. He agreed to stay away because of the controversy surrounding the recording published Saturday on the TMZ website. The Clippers lost 118-97 to the Golden State Warriors.
Over the weekend, players expressed outrage.
"As an owner, I'm obviously disgusted that a fellow team owner could hold such sickening and offensive views," said Michael Jordan, now the owner of the Charlotte Bobcats. "... As a former player, I'm completely outraged. There is no room in the NBA -- or anywhere else -- for the kind of racism and hatred that Mr. Sterling allegedly expressed."
Abdul-Jabbar, who was a Clippers special assistant coach in 2000, said he wasn't shocked by the controversy.
"I know him. I know his voice," he told CNN. "I am not surprised by this very much."
But Abdul-Jabbar said that Sterling is a congenial person and that he never heard Sterling say anything racist.
He said he thought the recording showed a "repugnant attitude for someone to have, and for him to be an employer for so many people of color, it kind of blows your mind."
Magic Johnson, speaking on an ABC pregame show Sunday, said Sterling needs to go.
"He shouldn't own a team anymore. And he should stand up and say, 'I don't want to own a team anymore,' " Johnson said.
Miami Heat forward LeBron James spoke to reporters before the playoff game against the Charlotte Bobcats.
"If the reports are true, it's unacceptable. It's unacceptable in our league," he said. "It doesn't matter if you're white, black, Hispanic, whatever, all across the races. It's unacceptable, and as a commissioner in our league, they have to make a stand, and they have to be very aggressive with it."
Iconic former players Shaquille O'Neal and Charles Barkley discussed the controversy during the Atlanta Hawks-Indiana Pacers halftime program on TNT, which, like CNN, is a division of Time Warner.
"Should this guy continue to be an owner?" O'Neal asked. He called the comments "repugnant."
"We cannot have an NBA owner discriminating against the league," Barkley said. "We're a black league."
'Is that racism?'
In the recording on Deadspin, a man and woman talk about the photos, and he tells her he cannot change cultural beliefs.
The woman says she doesn't think the man is racist but the people around him have "poison minds."
"It's the world! You go to Israel, the blacks are just treated like dogs," the man says.
He says there are white Jews and black Jews, and they are treated 100% differently.
"And is that right?" the woman asks.
"It isn't a question -- we don't evaluate what's right and wrong, we live in a society. We live in a culture. We have to live within that culture," the man replies.
When the woman says she doesn't share the man's views about race, he tells her: "Well, then, if you don't feel -- don't come to my games. Don't bring black people, and don't come."
The woman, who says she is of mixed race, reminds him that most of his team's players are African-American.
"I support them and give them food, and clothes, and cars, and houses. Who gives it to them? Does someone else give it to them? Do I know that I have -- who makes the game? Do I make the game, or do they make the game?"
The woman compares racial discrimination to the Holocaust.
"And you're Jewish. You understand discrimination," she says.
The man disagrees with the analogy and says that what he's talking about is not discrimination.
"There's no racism here. If you don't want to be walking into a basketball game with a certain person, is that racism?" the man says.
Chris Paul, a Clippers player and the National Basketball Players Association president, issued a statement Saturday, saying "this is a very serious issue which we will address aggressively."
Investigation under way
NBA Commissioner Adam Silver said Saturday that Sterling, who has owned the basketball franchise for nearly three decades, is now under investigation over the comments attributed to him.
Silver said that the league's investigation will seek to determine whether the audio is authentic and to figure out the context in which these "offensive and disturbing" comments were made.
But he cautioned that Sterling must be afforded due process, so he would not speculate on any possible punishment but said that the investigation will move "extraordinarily quickly."
Clippers President Andy Roeser on Saturday suggested a woman -- whom he doesn't mention by name -- was "getting even" with Sterling over a lawsuit.
Donald Sterling's wife, Rochelle Sterling, filed a lawsuit last month against Stiviano, who she said was having an affair with her husband.
In the complaint, Rochelle Sterling accuses Stiviano of targeting extremely wealthy older men. The suit claims that Donald Sterling used the couple's money to buy Stiviano a Ferrari, two Bentleys, and a Range Rover and that Stiviano took possession of a $1.8 million duplex through fraud. Sterling also gave her nearly $250,000 in cash, the court document says.
Stiviano countered in another court document that there was nothing wrong with Donald Sterling giving her gifts, and she never took advantage of the Clippers owner, who made much of his fortune in real estate.
Speaking about the recording, Roeser said, "We do not know if it is legitimate or it has been altered. We do know that the woman on the tape -- who we believe released it to TMZ -- is the defendant in a lawsuit brought by the Sterling family alleging that she embezzled more than $1.8 million, who told Mr. Sterling that she would 'get even.' "
Roeser said Sterling is upset and apologizes for sentiments attributed to him about Johnson. "(Sterling) has long considered Magic a friend and has only the utmost respect and admiration for him -- both in terms of who he is and what he has achieved."
Sterling is "emphatic that what is reflected on that recording is not consistent with, nor does it reflect his views, beliefs or feelings," Roeser said.
President Obama's response
President Barack Obama weighed in on the controversy.
At a news conference with Malaysian Prime Minister Najib Razak on Sunday, Obama was asked about the comments on the recording.
"When ignorant folks want to advertise their ignorance, you don't really have to do anything, you just let them talk. That's what happened here," the President said.
Obama also said Sterling's alleged comments are an example of how "the United States continues to wrestle with the legacy of race and slavery and segregation."
The president of the California NAACP suggested that fans boycott Clippers games.
"We also suggest that African-Americans and Latinos should honor (Sterling's) request and not attend the games," Alice Huffman said in a statement released Saturday.
Sterling was to receive a lifetime achievement award at an event next month to mark the 100th anniversary of the Los Angeles NAACP, but the national organization tweeted Sunday that wouldn't happen.
The release of the recordings comes at a bad time for the Clippers, who are playing in the first round of the NBA playoffs.
"I don't know if I'm surprised or not," Clippers head coach Doc Rivers said at the team's practice Saturday, adding that he "obviously" didn't like the comments.
Rivers, who is in his first year coaching the team, told reporters that he didn't want the controversy to detract from the playoffs. He would be the sole person speaking on behalf of the team, he said.
CNN's AnneClaire Stapleton, Joe Sutton and Kevin Dotson contributed to this report.
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