Boone appeared in eight games in 2021 and rushed four times for 35 yards while catching his only two targets for 22 yards.
Boone missed the first five games of the 2021 campaign with a quadriceps injury he suffered before the season in training camp. When the veteran running back made his return to the field, his involvement was minimal as a result of the near-even backfield split between Melvin Gordon and rookie Javonte Williams. Both backs had a strong year, so Boone played a depth role for the games in which he was active while also contributing on special teams. Boone is entering the second year of his two-year contract he signed in March of 2021, so he will likely be a member of the Broncos next season. Gordon, however, is set to become a free agent this offseason. It's possible that Boone could become Denver's de facto No. 2 running back behind Williams if Gordon signs with another team. In that scenario, Boone would hold some value in 2022 as a change-of-pace back for a team that runs the ball effectively.