LOS ANGELES -- Donald Sterling said Tuesday he believes his wife, Shelly Sterling, is only selling the Los Angeles Clippers because she is "terrified and frightened of this NBA" and that if he were to sell the franchise, he could get $2.5 billion to $5 billion because of a boom in media-rights fees.

"Do you think Microsoft is foolish? Do you think they don't think and wonder where they're going to get the money back?" Sterling asked during a contentious hourlong testimony in a Los Angeles probate court. "There's no ego involved here. There's tremendous opportunity."

At the end of this week's trial, Judge Michael Levanas will decide if Shelly Sterling was authorized to sell the franchise to former Microsoft CEO Steve Ballmer for a record-setting $2 billion on May 29. Her attorneys contend that she followed all of the procedures outlined in the Sterling Family Trust -- which owned the team and the other assets the couple has accumulated in nearly six decades of marriage -- when two neurologists examined her husband and determined he was mentally incapacitated and unfit to conduct his own legal and business affairs.

Donald Sterling and his attorneys dispute that, arguing that the exams were conducted under false pretenses because he was not informed the results could later be used to exclude him as a trustee. His lawyers also argue the doctors violated federal privacy laws by disseminating the results of his exams to attorneys in the case, and that their testimony and findings should not be admissible.

Both doctors testified in the case Monday and Tuesday, but the drama peaked when the 80-year-old owner took the stand.

Sterling failed to appear in court Monday, prompting Shelly Sterling's lead attorney, Pierce O'Donnell, to suggest a bench warrant be issued for him. He arrived Tuesday, wearing a black suit and sunglasses, midway through the testimony of Dr. J. Edward Spar, the man whom he'd left an angry voicemail for on June 9 and threatened to have fired from his job at UCLA for releasing his medical records.

Shelly Sterling arrives for trial on Tuesday. At one point, she approached husband Donald Sterling and exchanged pleasantries. AP Photo/Nick Ut

Donald Sterling sat patiently for over an hour in the sweltering courtroom, which was filled to capacity with reporters and curious onlookers. During a recess, Shelly approached him, touched his shoulder and the two exchanged pleasantries.

Donald Sterling was then called to the stand and questioned by legendary entertainment attorney Bert Fields and seemed to relish the opportunity to spar with the man who has a reputation for making even the most powerful men in Hollywood squirm on the witness stand.

Before the questioning began, Judge Levanas permitted the attorneys to take their jackets off and promised there would be fans in the courtroom one day. The 85-year-old Fields removed his jacket. Sterling unbuttoned the top buttons of his shirt. Later he asked for a bottle of water and tissues.

From the beginning, Sterling was combative and defensive. After Fields' first question, Sterling said, "Is that a compound question?"

Levanas intervened.

"I know you're a lawyer and a lawyer likes to control what goes on," the judge told Sterling. "If you don't understand a question, let me know. But don't suggest a question is compound or not compound. It's going to take a long time."

Sterling nodded and said: "I'll observe that, your honor. It's just that he asked me three questions in one, so forgive me, I won't let that happen again."

But at every turn, Sterling sought to spar with Fields, calling him a "smart-ass" and belittling him with responses like, "I'm talking about your questions. I'm sure they'll improve."

While Levanas noted that Sterling's responses were "entertaining" to the raucous courtroom, which laughed amid the chattering of typing on laptops, he continually tried to keep the proceedings moving along. And between the angry rants toward the NBA and the doctors who had examined him, and emotional declarations of love for his wife, Sterling addressed and answered several key issues in the case.

"The only one I trust is my wife," he said. "I love her. She's a good person. If there was a fly in the house, she'd open up 10 windows to let it out."