"As I walk away from the sport of boxing today, I leave at the top of your glorious mountain, which was always my vision and my dream. I did it. We did it," Ward wrote in one of the social networks.
"From the bottom of my heart, thank you to everyone who has played a part in my journey. You know who you are. I could not have done this without you. 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.
"If I cannot give my family, my team, and the fans everything that I have, then I should no longer be fighting. Above all, I give God the Glory, for allowing me to do what I've done, for as long as I have."
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