Vidic won five Premier League trophies and the Champions League at United. Van Dijk has won a solo Champions League, and was on his way to tasting Premier League glory this campaign before the outbreak of the coronavirus brought the season to a halt.
When asked to name the better of the two, Leboeuf told ESPN FC: "I would go for Van Dijk. I think he's more complete.
"I loved Vidic, because I think he was a dog, and a fantastic defender. But Van Dijk can lead the team and has range.
"I don't think Vidic was capable of doing that. Hats off to Vidic, though."