Flowers was hurt in a 23-20 home loss to Kansas City on Sunday.
The Chargers' secondary isn't in great shape heading into the matchup against record-setting quarterback Peyton Manning.
Asked if Richard Marshall would start for Flowers, coach Mike McCoy said: ''We're going to wait until tomorrow and we'll have the best 46 out on the field.''
Running back Donald Brown will miss his third straight game due to a concussion.
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