Selected by the Packers in the third round of the 1965 NFL Draft, Brown injured his shoulder at the College All-Star camp, underwent surgery and missed the entire season. He played in five games in 1966 before undergoing knee surgery and missing the remainder of the season. Still troubled by knee problems in 1967, Brown played sparingly in 14 games, but was injured in the season finale and underwent surgery to have his spleen removed.