Story highlights Cleveland Clinic doctor finds Donald Sterling does not have Alzheimer's or dementia

Neurologist concludes Sterling does have mild cognitive impairment

Sterling attorneys are due in court on Monday, a week before the trial over his mental capacity

A new doctor has declared Los Angeles Clippers owner Donald Sterling mentally fit after a comprehensive medical examination in Las Vegas over the weekend, CNN confirmed through a source with knowledge of the situation.

The exam was conducted by Dr. Jeffrey Cummings, a neurologist with the Cleveland Clinic and one of the top dementia and Alzheimer's disease specialists in the country, according to the source.

Cummings determined Sterling has no signs of dementia and no lack of mental capacity, but he did show signs of MCI, mild cognitive impairment, which is common in people Sterling's age, the source said.

Sterling is 80 years old.

The testing, arranged by one of Sterling's attorneys, lasted more than an hour, the source added, and found no indication Sterling can't manage his business affairs.

The latest medical exam follows a previous diagnosis by two other doctors, engaged by his estranged wife Shelly Sterling, that determined Sterling is mentally incapacitated.

Cummings, the source said, has agreed to testify at the trial over Sterling's mental capacity, which is scheduled for July 7th.

Shelly Sterling filed a lawsuit in a dispute over the sale of the team with her estranged husband, asking a Los Angeles court to uphold her deal to sell the Clippers to former Microsoft CEO Steve Ballmer for $2 billion.

She contends her husband is incapacitated by the onset of Alzheimer's or another brain disease.

The couple co-owns the basketball team. If one of the trustees is declared mentally incapacitated, the other becomes the lone trustee, according to records. His wife used that provision to negotiate the deal with Ballmer.

Sterling's attorneys are due in court Monday afternoon for a hearing on legal jurisdiction in the case. They also plan to ask for a postponement in the start of the trial.

Donald Sterling made national headlines in early April when a website leaked a phone recording of Sterling making racist comments to a friend. After the recording surfaced, the NBA banned him for life and fined him $2.5 million.