Cris "Cyborg" Justino came back with some harsh words after being called a "proven cheater" by Germaine de Randamie's camp Friday.
In a series of tweets, Justino questioned everything from the legitimacy of the featherweight title to her toughness.
"We waited five months to find out it wasn't [de Randamie's] hand that was hurt but her mental toughness and lack of confidence," she tweeted. "The toughest opponent de Randamie will ever fight is her mind. Unfortunately that's a battle she will have to overcome before being world champ."
She added, "Some people are so afraid to lose that they will find every excuse not to try.