The veteran was missing at St Mary's Stadium with a cut shin as the Saints condemned the Reds to a 3-1 defeat.
Rodgers admits that he is not quite comfortable with his options in central defence and feels that the whole team need to concentrate more to help the back four.
When asked if his side missed Carragher, he told The Mirror: "There's no question. For us, it's an area we feel we need to be better in.
"They'll be disappointed of course, as defenders, when we concede goals. We've been in a run of late where we either don't concede or we do, two or three. So it was one where our defensive line always starts from the front of the pitch. This is a group, when we lose, we lose together."
Defeat at Southampton saw Liverpool slip to seventh in the Premier League, three points behind city rivals Everton.