The San Francisco 49ers were the best offense in the NFL when operating out of 21 personnel last season, according to ESPN analyst Matt Bowen.
This personnel grouping includes two running backs, one tight end and two wide receivers on the field at once. Typically, one of those two running backs on the field is a fullback, who can create run-game leverage through key blocking assignments, while also setting up play-action plays that mirror backfield action to open up holes in coverage for the tight end and receivers. The look can also shift easily into 12 or 11 personnel to exploit matchup advantages against base defensive fronts.
No team used it better than San Francisco. Per ESPN, the 49ers ran 179 pass attempts and 206 rush attempts out of the grouping, totaling 2,248 yards and 14 touchdowns — the most snaps of any team in the league.
It’s a staple of coach Kyle Shanahan’s offense. The 49ers had a league-high 35.84 EPA, 21 explosive passes and 19 explosive rushes in the grouping last season. With the versatility of fullback Kyle Juszczyk, Shanahan can create run game advantages while leaning on his play-action pass concepts and the receiving traits of running back Christian McCaffrey.
Juszczyk has been a cornerstone of Shanahan’s system for years, and made the Pro Bowl in all nine of his seasons with the 49ers, as well as two first-team All-Pros in the past three years. McCaffrey, when healthy, is one of the most dangerous receiving backs in the league — a matchup problem that opposing defenses simply cannot account for with a single player.
Most of the same offense is back in 2026, as well as new receivers and running backs. This should give Shanahan every reason to lean on his most productive personnel grouping once again.
This article originally appeared on Niners Wire: NFL personnel groupings: 49ers dominated in 21 personnel in 2025
