Said Coach Doc Rivers: “He’s brought credibility to this franchise.”

At courtside a few hours before the Clippers-Thunder game, Ballmer explained that he had always been passionate about basketball and had long wanted to buy a basketball team. What held him back, he said, was his “day job.”

In 2008, when Howard Schultz, the Starbucks chief executive and an owner of the Seattle SuperSonics, decided to sell the team, Ballmer joined a group of Seattle businesspeople who tried to buy it. That effort failed, and the Sonics were sold instead to a consortium of Oklahoma City businessmen, who promptly moved it to their hometown.

Five years later, when the Maloof family put the Sacramento Kings on the block, Ballmer wanted to buy the team and move it to Seattle. But David Stern, the N.B.A. commissioner, and Adam Silver, his deputy, told him they wanted an owner who would keep the Kings in Sacramento.

When Ballmer retired in 2014, he became more focused on buying a team. He approached Silver, who had just succeeded Stern, to ask if the league had any expansion plans. No, Silver told him, suggesting that he think instead about buying an existing franchise in a city he was willing to travel to. Ballmer considered Milwaukee but concluded that the two-time-zone commute would be too draining.

It was right about then that TMZ got hold of a taped phone conversation between Sterling and his mistress, V. Stiviano, in which the Clippers owner made a series of deeply offensive racist remarks. Though Sterling didn’t want to sell the team, the pressure to do so was intense, and it came not just from the league and the players, but also from his wife.

Through the auspices of Michael Eisner, the former Disney chief executive and a die-hard Clippers fan, Ballmer got in touch with Shelly Sterling, who was managing the sale. The two hit it off and began negotiating a deal. Ballmer never asked to see the team’s balance sheet — he really didn’t care about that. She was talking to other potential buyers, of course. Although Ballmer had bid well over $1 billion, he told me that he’d heard that someone was going to offer $1.8 billion So he increased his bid to $2 billion. That sealed the deal.