A graduate of Center High School and the University of Iowa, Vlasic was selected 88th in the 1987 NFL Draft by the San Diego Chargers. He was a backup for Dan Fouts during his first season, then started two games the following year. After not seeing playing time in 1989, Vlasic started the season opener in 1990, his last year with San Diego. He played for two seasons with Kansas City and one with Tampa Bay, but was released in 1994, having not had actual playing time since 1991.