Henderson is currently suffering with a hip problem, while Coutinho is attempting to recover from a groin strain.
The pair could yet feature tomorrow night when Boro visit Anfield, but Rodgers does not expect them to be a part of his plans.
"We just need to assess one or two," he told reporters on Monday afternoon. "Jordan Henderson picked up a knock so we need to assess where he's at and Philippe Coutinho is highly unlikely for tomorrow as well."
The Reds reached the third round of last season's competition before losing to old rivals Manchester United.