His numbers would increase steadily over the next two NFL seasons. In 1984 he started in 11 games, notching 60 tackles and 6.5 sacks. He also forced two fumbles that season. For the 1985 campaign, Marshall was a full-time starter at end, nearly reaching 100 tackles (he had 99), a whopping 15.5 sacks and a pick.
Marshall was, of course, a key cog in the defensive machine that rolled to the Super Bowl Championship against the Denver Broncos after the 1986 season. He picked up three sacks in those playoffs.
Over a ten season span with the Giants, Marshall started in 123 of 149 games during the regular season, garnering 660 tackles, 79.5 sacks, and two interceptions with 9 forced fumbles.
Marshall, at the time of this writing, is third on the Giants' all-time sack list, behind only Michael Strahan and Lawrence Taylor.