Pound-for-pound king and unified light heavyweight world titleholder Andre Ward said in a statement on his website that he is "leaving" boxing.
"I want to be clear - I am leaving because my body can no longer put up with the rigors of the sport and therefore my desire to fight is no longer there," the statement said. "If I cannot give my family, my team, and the fans everything that I have, then I should no longer be fighting."
Last month, Ward told ringside media that his television contract with HBO is up.
He added that, contrary to industry chatter, he remains under contract with promoter Roc Nation Sports, even though rumors have swirled that he was gearing up for a jump to Top Rank.