Masvidal is suspected of felony battery in connection with an altercation Monday, according to a Miami Beach police report obtained by ESPN. The other person involved, who lost teeth, wasn't identified after invoking that right under Marsy's Law, Miami Beach Police Public Information Officer Ernesto Rodriguez told ESPN.
Masvidal tagged Covington in a tweet and said in the accompanying video: "You talk that s---, you got to back it up. That's how my city rolls, man."
TMZ, which obtained video from the incident that shows police at the scene in front of Miami Beach hot spot Papi Steak, caught Covington on camera saying: "He's over here swinging, trying to come at me, and I ran. ... How would he know I'm here?"
Masvidal's manager, Malki Kawa, didn't respond to a message seeking comment.
The other person told police, after they responded at 10:55 p.m. ET, that he was attacked by Masvidal as he was walking away from the restaurant. According to the person, Masvidal ran up from the left and sucker-punched him twice. One punch was to his mouth and the other to his left eye. During the attack, the person said, Masvidal told him, "You shouldn't have been talking about my kids." Masvidal repeated a similar statement on social media.
The person suffered a fractured left tooth and an abrasion to his left wrist. Masvidal, according to the person's account, was wearing a blue surgical mask and a hoodie that covered his head. He was able to identify Masvidal, he said, because of his trademark curly hair that flowed out of the hoodie in addition to his voice and the upper half of his face.
Masvidal, 37, is from Miami, while Covington now resides in the city. The friends-turned-enemies exchanged heated words in the lead-up to their UFC bout, which was named Fight of the Night.
The defeat was Masvidal's third consecutive, including two losses to Kamaru Usman, in his attempts to win the UFC welterweight championship. He signed an extension with UFC before the fight.
Covington, 34, rebounded from his own loss to Usman with the victory over Masvidal. He's currently ranked No. 2 by ESPN at welterweight.