Technically, he did not. He punched him, but did not take him out. Later on, he hit him with a chair, repeatedly.

The One Punch take down is exactly what it says on the tin. One Punch, Guy Gardner on the floor, cold. Batman is still the godsdamned Batman. :)

Also, if Marcone is to be Batman, he is contractually obligated to be a bigger badass than the superpowered guy annoying him. Hence the One Punch. :D