A user on the Reddit messageboard had posted the photo with the comment "One US rower was particularly excited by his Bronze medal..." prompting a response from Rummel.
Henrik Rummell - centre
"This is me and I swear it's not erect!" Rummel posted under the Rummelator username.
"I don't know why it ended up in that position but there you go."
Another user responded: "Dude when you win a medal in the goddamn olympics your penis can be however you want. You earned it."
Asked for proof that he was in fact the rower, Rummel posted a photo of himself holding a piece of paper with the username and today's date (August 7).
Rummel's previous posts on Reddit have included rowing advice for fellow users and his opinion on Danny Boyle's Opening Ceremony.
"The industrial thing blew my socks off! Really cool!" he said after the extravaganza.
London 2012 Olympics - photo gallery:
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