On April 4, 1995, the Dolphins traded a second and third-round draft pick for Armstrong. He was acquired to fill a role as a designated pass rusher, a player who comes into the game in likely passing downs in an effort to give the team's pass rush a boost. This is a role Armstrong filled the rest of his career; however, in five seasons, injuries to the starting ends forced Armstrong into a starting role. On October 12, 1995, Armstrong signed a five-year $8.9 million contract extension with the Dolphins.
