The term "super bowl slump" in fantasy football describes a widely believed curse in which the previous champion of a fantasy football league struggles mightily the following year. The concept also pertains to drafting players, as managers tend to believe a player that has just won a Super Bowl in real life is likely to underperform the very next season.
Struggling to win fantasy football matchups the year after winning the championship can often be attributed to recency bias. Fantasy managers tend to dwell on player performances from the previous season, trying to recreate the same roster in hopes of winning another league trophy. This is not an effective strategy, as player roles and the talent level of their real-life teams tends to change from season to season. For example, a running back that put up astronomical fantasy numbers in the playoffs might have to share time with a talented new running back signed in free agency. Teams can also lose players to free agency, leaving them without many of the skilled players that led them to great success.
Many fantasy managers that are aware of the Super Bowl slump often try to overcompensate with a contrarian approach. They lessen their expectations for players coming off a real-life Super Bowl victory and avoid selecting them in the draft. While this particular strategy works in some cases, it can also cause managers to miss out on star players that consistently score lots of fantasy points regardless of the situation.