[1] Born in South Gate, California, Horn graduated from Gardena High School in Los Angeles in 1963, where he starred in football and baseball for the Mohicans.
Horn transferred to San Diego State College and played under head coach Don Coryell.
Horn relieved injured back-up Zeke Bratkowski in the first quarter and guided the Packers to a one-point win over the Chicago Bears at Wrigley Field, which denied them the division title.
[10] Horn finished his pro career in 1975 with the Portland Thunder of the soon-defunct World Football League (WFL), where he completed 158 of 272 passes for 1742 yards and 11 TDs and 12 picks.
[1][14] During a conversation in 2008, Horn talked about the excitement he felt when he was selected by the Green Bay Packers as their first round draft choice with a contract for $15,000 in 1967.