The "2019 Iowa State Defense" was a standout unit in college football, orchestrated by head coach Matt Campbell and his defensive staff. This defense was characterized by its strategic flexibility, utilizing a base 3-3-5 alignment that could morph into various formations depending on the opponent's offensive scheme. This adaptability was key in making Iowa State's defense one of the toughest in the Big 12 Conference. The 3-3-5 setup, with an extra defensive back on the field, allowed for better coverage against the pass-heavy offenses prevalent in college football, while still maintaining a solid front against the run. Under the guidance of defensive coordinator Jon Heacock, this unit was known for its aggressive play calling, often blitzing from unexpected angles, which kept opposing quarterbacks on their toes. The defense was particularly effective in creating turnovers, with a knack for intercepting passes and recovering fumbles, which significantly contributed to Iowa State's success that season. Key players included safety Greg Eisworth, who was pivotal in the backfield, and linebacker Marcel Spears, who was instrumental in stopping the run and blitzing. This defense played a significant role in Iowa State's memorable victory over Oklahoma, where they managed to keep the game close through strategic plays and resilience. However, they also faced challenges, particularly in games where they couldn't sustain their defensive pressure, leading to mixed results against tougher opponents. Overall, the 2019 Iowa State defense was a study in strategic depth, player versatility, and the effectiveness of a well-coached unit, setting a benchmark for how defenses can evolve in modern college football.