They say defense wins championships, and the past two title winners -- the 2024 Philadelphia Eagles and 2025 Seattle Seahawks -- can attest to that. One allowed the fewest total yards during the regular season and the other the fewest points, and both put forth dominating defensive efforts in their Super Bowl victories.
But while that's all well and good in the on-field game, defenses carry nowhere near the same level of importance in fantasy football.
As a team-oriented position, Team Defense/Special Teams (or D/ST) are a volatile bunch. They are subject to the league's any-given-Sunday mindset, where injuries, coaching, defensive scheme, opponent, weather and travel can wildly swing the weekly results. This is not a position at which you can lock in a single D/ST and expect to successfully navigate 17 weeks.
To that point, it has been 13 years since the D/ST selected first on average in ESPN leagues actually scored the position's most fantasy points. In fact, of the past 10 D/STs picked first, only three even finished among its top five in scoring.