Coach Gus Bradley ruled Gerhart out Wednesday, two days before the game.
Gerhart has missed the last five days of practice because of a hip flexor injury. Without him, journeyman Jordan Todman has been getting repetitions with the first-team offense.
The Jaguars gave Gerhart a three-year contract worth $10.5 million in March to replace Maurice Jones-Drew. Gerhart spent the last four years backing up All-Pro running back Adrian Peterson in Minnesota, totaling 1,305 yards rushing and five touchdowns.
Jacksonville signed him to be its starter, expecting him to get around 15 to 20 carriers a game.
Now, though, the Jags are just trying to get him healthy enough to practice and play.