Medical personnel attended to the fan, delaying the start of the eighth inning Tuesday night. The man had a brace around his neck as he was wheeled off.
The Brewers say the fan was conscious and alert, and was being taken to Froedtert Hospital.
Fans can watch the game from a dining area above the Milwaukee bullpen beyond the wall in left-center. The concourse, which is at least 15 feet above the bullpen, is lined with a metal railing roughly four feet high.