Amanda Nunes fought HARD to win a new belt at UFC 215 ... and immediately gave up her gold when she met a fan with an amazing story.
19-year-old cancer survivor -- and UFC superfan -- Angie Rose talked about their meet-up on social media ... describing the incredible act of kindness from the UFC women's bantamweight champ.
After the post-fight press conference, Angie says she waited in the rain by the fighters' exit tunnel at Rogers Place in Edmonton. Nunes spotted Angie ... and told her bus driver she had to meet the girl.
Angie says she gave Amanda a couple homemade bracelets ... and in return, Amanda gifted Angie her newly won strap and told her she was "the real champion."
"Hearing those words mean so much to me after I have battled through 9 years of sickness, sadness, pain and suffering with off again, on again cancer," Angie wrote.
Angie added that her dream is to meet Conor McGregor next.