Fifty-one-year-old Stuart S. Springstube of Weyauwega was reaching over a railing for foul balls April 25 while the Chicago Cubs took batting practice.
He fell over the railing to the hard dirt below.
A medical examiner's report released Friday says Springstube suffered a brain hemorrhage and died Wednesday.
A Brewers spokesman said Springstube had been moving his extremities after the fall. A trainer said Springstube was cut and bleeding from the face but conscious as he was taken off the field.
The Milwaukee Journal Sentinel says the report gives no indication Springstube was intoxicated or impaired.