Mullens completed six of seven passes for 65 yards in Friday's 34-17 preseason loss to the Panthers.
The Jaguars rested their starters in this one, so Mullens was under center for the first quarter and led the offense on one field-goal drive in two possessions before turning things over to Carter Bradley. Mullens figures to be the No. 2 quarterback this year behind Trevor Lawrence, a role that may not require him to see much action -- Lawrence has played all 17 regular-season games in three of his five NFL seasons.