Popeye blurb up and yeah, its not looking good for one punch. Popeye has toonforce that lets him alter reality with his fist, giving the sun a black eye and such. Unless they go with the whole philosophy thing where they try to say, "Well, saitama is designed around always being too strong and able to defeat anything in one punch therefore blah blah blah" All they need to do is bs their way into quantifying one of popeyes absurd feats like moving constellations around and saying one punch has never done anything that powerful and thats the end. But at least the caped baldy will be happy he finally found someone he couldnt crush.