Allen completed seven of 13 pass attempts for 98 yards while getting the nod under center in Saturday's preseason tilt against Tennessee.
San Francisco rested most of its starting offense Saturday, allowing Allen to start the first half and journeyman backup Joshua Dobbs to handle the remaining snaps. The latter (14-of-20 for 146 yards) looked better in the competition to be Brock Purdy's backup, but Allen had to face the opponent's starting defense and was also saddled with two incompletions due to drops. Neither signal-caller will be on fantasy radars come Week 1, as Purdy will be running the well-oiled machine that is the 49ers' offense when the regular season kicks off.