What person do you think has givin Luffy the hardest struggle in a one on one fight. In my opinion I think its Crocodile. He defeted Luffy TWICE and still gave him a run for his money the third time. But then again it might be Lucci, I mean... come on!! That fight was amazing. Or perhaps Megallan? OH what about Aokiji?? Hmmm I just cant decide... Maybe its someone I havent even thought of yet. But to reiterrate, who do You think gave Luffy his toughest one-on-one struggle??