That there are people in here who actually believes that just because he has haki, he can defeat an Admiral.... Even if we say he is able to land a punch, do you really think Luffy's level of Haki is enough to hurt them? You'd need Haki like Rayleigh's or WB's etc. to pull it off. People need to look past the DF's and notice that there are powerscalings in OP!