The proposed sale of the Los Angeles Clippers for $2 billion could be complicated by current co-owner Donald Sterling, who may file a lawsuit over the deal. The wife of the L.A. billionaire, Shelly Sterling, signed a binding agreement late Thursday to sell the NBA team to Steve Ballmer, former Microsoft chief executive, for $2 billion. The deal must be approved by the National Basketball Association, which is scheduled to meet on the matter next week. Sterling was evaluated by neurologists earlier this month, and, according to media reports, Shelly was given complete control of the Clippers following the diagnosis that her husband was mentally incompetent per the terms of the Sterling Family Trust, the entity through which the couple owns the basketball team. An attorney representing Donald Sterling rejected the claim the Clippers owner is mentally incompetent, setting the stage for a legal showdown over the sale of the team. “Mr. Sterling is far from mentally incompetent,” Max Blecher wrote in an email to ESPN’s Ramona Shelburne. He called the results of Sterling’s diagnosis “grossly exaggerated.” NBC News reported that Sterling will file a lawsuit late Friday seeking $1 billion in damages against the NBA because it is forcing him to sell the team. It’s believed that the league will approve the Ballmer bid if the new owner agrees to keep the team in Los Angeles, which Ballmer has said he will do. The controversy over the Clippers’ ownership began when Sterling was recorded telling his mistress, V. Stiviano, that he didn’t want her bringing black people with her to the games. The NBA quickly fined Sterling, banned him for life and moved to force a sale of the team.