(CNN) -- Donald Sterling -- the longtime owner of the Los Angeles Clippers -- is under investigation by the NBA for "offensive and disturbing" remarks he allegedly made about African-Americans.
Sterling, who has owned the franchise for nearly three decades, made the comments in a 10-minute argument he had with girlfriend V. Stiviano on April 9, according to TMZ, which posted the audio late Friday.
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.
Clippers president Andy Roeser on Saturday questioned the recording and suggested a woman -- whom he doesn't mention by name -- was "getting even" with Sterling over a lawsuit.
NBA commissioner Adam Silver said at a press conference in Memphis on Saturday night that the league's investigation will seek to determine whether the tape is authentic and to figure out the context in which these "offensive and disturbing" comments were made.
Silver cautioned that Sterling must be afforded due process, so he would not speculate on any possible punishment, if any -- but said that the investigation will move "extraordinarily quickly."
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."
TMZ does not say who made the recording or how the celebrity-centric website obtained it.
Attempts to reach Stiviano on Saturday were unsuccessful. She is part African-American, according to the recording.
The man alleged to be Sterling takes particular exception to a photo she posted to Instagram with NBA icon Earvin "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."
Johnson responded Saturday afternoon via his verified Twitter account.
"I feel sorry for my friends Coach Doc Rivers and Chris Paul that they have to work for a man that feels that way about African Americans" read a tweet from @MagicJohnson. "I will never go to a Clippers game again as long as Donald Sterling is the owner," read another.
Roeser said that Sterling is upset and apologizes for sentiments attributed to him about Earvin 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.
"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 distract from the playoffs. He said he would be the sole person speaking on behalf of the team.
The players union's response will be led by NBA player-turned-mayor of Sacramento Kevin Johnson. "The reported comments made by Clippers owner Donald Sterling are reprehensible and unacceptable," he said in a statement.
Former players universally denounced the recorded comments.
"Should this guy continue to be an owner?" asked Shaquille O'Neal, who also called the comments "repugnant."
"We cannot have an NBA owner discriminating against the league," said Charles Barkley. "We're a black league."
Both discussed the issue during the Atlanta Hawks-Indiana Pacers halftime program on TNT, which like CNN, is a division of Time Warner.
In an interesting wrinkle, Sterling is set to be given a lifetime achievement award at an event next month to mark the 100th anniversary of the Los Angeles NAACP.
The Clippers are set to play the Golden State Warriors in Oakland on Sunday in the fourth game in their best-of-seven playoff series. Silver said Sterling has agreed to not attend.
Golden State head coach Mark Jackson said that he was "disappointed in the comments made. I think there's no place in society for those feelings."