While James Cook is very talented, he does not have the size to be a bruising running back that can carry the ball 15-20 times a game. The Bills have utilized Latavius Murray in this role as of late but it might finally be time for Leonard Fournette to establish a place in this backfield.
The Bills signed Fournette recently to the practice squad but he has not been elevated yet to the active roster on game day. After a few weeks of practice, Fournette might be in position to finally be active and play on game day.
In 2020, the Panthers lost Christian McCaffrey for the season after only three games but were able to keep the run game productive with Mike Davis. At the time, he was primarily just a backup but would run for 642 yards and six rushing touchdowns in 15 games while also catching 59 passes on the season with two receiving touchdowns.
Leonard Fournette is similar to Davis in that he is a big running back who can also catch the ball out of the backfield. The last two seasons with the Bucs he had 69 and 73 receptions. The Buffalo Bills don't need to split the pass and run plays evenly to have balance but if they can establish the run, it will open up the rest of the offense.