Leonard Fournette is very good, but unless he gets some space in between the tackles, he can't do much.
The fullback is a dying position in College Football. There's no way around it. It started with the move to West Coast offenses in the early 2000's, and is becoming nearly total with the switch to Spread offenses in the modern game. Fullbacks have been substituted for staggered tight ends and wide receivers spreading the field. The LSU Tigers are one of the last teams in the nation to have a fullback that plays consistently. For us, this presents a problem, as LSU's fullbacks are pretty good, even though we don't know which one we'll see.