Dils was drafted by the Minnesota Vikings in the fourth round of the 1979 NFL Draft. In his second year with the club, he made his first start filling in for an injured Tommy Kramer and led the Vikings to a win over the Washington Redskins, a game which proved crucial to Minnesota's playoff run that year. He played six seasons with the Vikings and started most of the 1983 season, where he was paired in the backfield with former Stanford teammate Darrin Nelson. He was traded to the Los Angeles Rams in 1984. He spent his final full season with the Atlanta Falcons before retiring with the Rams before the 1989 regular season began.