The Greater of Two Evils: Loss of Landry Jones or Travis Lewis?

All I said was "At least it wasn't Landry Jones." and the fight was on. My buddy contended that Lewis is the heart and soul of a young defense and that no one on the roster can replace his combination of experience, knowledge, or leadership. I countered that Jones is just as irreplaceable and is an integral part of over 75 snaps each game. The argument went back and forth and is still unresolved. The loss of either could, and in the case of Travis Lewis will, jeopardize a win in any game in which they don't play.

The question is: In your opinion, which player, Landry Jones or Travis Lewis, would constitute a greater loss over the