Allen (shoulder) has been ruled out of Sunday's game against San Francisco.
Allen has been one of the best defensive players for the Jaguars this season, so there's no question his absence will be greatly felt. This will mean Shaquille Quarterman might be in line to see a few extra snaps behind starters Damien Wilson and Myles Jack, though Chapelle Russell might also be in contention for a slight uptick in playing time.