Multiple outlets in Oklahoma reported Hilger had been battling cancer in recent years.
Hilger guided Oklahoma State to its first 10-win season in 1984. He passed for 3,982 career yards, 24 touchdowns, and 23 interceptions from 1981 to 1984.
He was a sixth-round pick in the 1985 NFL Draft by the Los Angeles Raiders and played three seasons with the Raiders before stints with the Detroit Lions and Indianapolis Colts.
Hilger passed for 2,584 yards, 11 touchdowns, and 19 interceptions in 23 career games (14 starts). He made five starts for the Raiders in 1987 and nine for the Lions in 1988.
Hilger’s top season by yardage (1,558) and touchdown passes (seven) came for Detroit but he also was intercepted 12 times and completed just 41.2 percent of his passes.