Namor wins. He was manhandling Simon when Simon had help from Ares and Sentry.
I know some idiots will bring up the fight where Namor fought Wonder Man/Beast/Whizzer and Simon KOed him when his back was turned. Now let's put the fight in context, Namor was DYING and on borrowed time and his back was turned and he was in a conversation with Whizzer.
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Lake Ontario, NY
Great thought
I bet Namor would sacrifice the sea to beat Wonder Man.
At first Wonder Man's ions might evaporate the sea but Wondy might end up as a brown dwarf in power.
Wondy has knocked out Namor out... Manhandling aside, one has shown he has the ability to knock the other out. Question how many times have you ever actually seen Wonderman knocked out in a fist fight? It's rare... Namor, not so much.
Wonderman and Vision only survived because they were in the dead center of the bomb when it went off, creating a vacuum at the center of it (like some lucky Hiroshima survivors when America dropped an A bomb on the city). Vision explains it here : (please log in to view the image)
Another Wonder Man myth (first one being Hydrobase 'lifting feat') busted.
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..even the outer hells are indifferent matters for they bow only to potent and archaic Nodens.