In his second day on the stand in a trial to determine whether he can be declared mentally incompetent, Sterling shouted at attorneys for both sides Wednesday. Later, he raged at the wife who's seeking the right to sell his team.
"Get away from me, you pig!" Sterling yelled from the front row of the courtroom seats when wife Shelly Sterling tried to approach him after her own testimony. A judge admonished him to make no more comments.
In her testimony that is scheduled to continue Thursday, Shelly Sterling declared that despite being estranged in many ways she loves her husband of 58 years and still acts as his principal caretaker, especially in medical care.
She said she was frightened at the changes she saw in him while watching a CNN interview where he addressed the recorded racial remarks that began the league's efforts to remove him.
"I couldn't believe it, and I started crying," she said. "I felt so bad. I couldn't believe that was him."
She said she suggested radiological tests or imaging to examine his brain, and was told eventually that he had early signs of Alzheimer's.
She became slightly tearful as she described her understanding of the disease, which becomes progressively worse.
In his earlier testimony, Sterling denounced both his wife and the league, saying he will never sell the Los Angeles Clippers and vowing a lifetime of lawsuits against the league.
"I will never, ever sell this team, and until I die I will be suing the NBA for this terrible violation under antitrust," Sterling shouted from the witness box.
He said Shelly Sterling had told him to have psychiatric and neurological exams only because he had turned 80, and she was concerned for his health.
"She deceived me. I trusted her," Sterling said. "I never thought a wife wouldn't stand for her husband."
Donald Sterling's lawyers are challenging the authority of Shelly Sterling under the family trust to unilaterally cut a $2 billion deal for the team with former Microsoft CEO Steve Ballmer.
Before she made the deal, two doctors examined Donald Sterling and declared him mentally incapacitated and unable to act as an administrator of the Sterling Family Trust, which owns the Clippers.
NBA owners are scheduled to vote on the Ballmer deal on Tuesday. It's also the day that Ballmer's offer is set to expire - and there is no deal without the judge's approval of the sale.
A judge had estimated that the trial would be done by Thursday, but said that is now looking increasingly unlikely, and with scheduling conflicts preventing the trial from continuing Friday, the proceedings could come precariously close to the Tuesday deadline.
If the sale isn't completed by Sept. 15, the league said it could seize the team and put it up for auction.