There are actually some hints that he has advanced CoO, he knew Zoro and Sanji would attack King and Queen during the "stars take the stage", when he attacked both King and Queen (chapter 1006) Queen goes to his human form and apparently prepares to shoot Marco with his gun right after he hit King
After that more precisely
Then he goes to hit Queen straight away with High Speed. I assume he was going all out here, basicly, i mean he was facing 2 YCs
And then there is this moment where Marco doesn't dodge the bullet from a random dude, then Izo takes him out of the way and he says "i knew you would have my back"