Joe Mixon told police, "It felt like a dude hit me" when he was slapped by a female student in 2014 ... and that's why he hit back.
Officials have released video of Mixon's interview with police investigators, shot in 2014, in which the Oklahoma football star tells his side of the story.
Mixon says the whole thing began that night when the female student blew smoke in his face and he went to confront her about being "disrespectful."
Mixon says a male member of the woman's group, who he believes to be gay, called him a "n**ger."
He responded by calling the man a "F*g."
He continued, "After that, the girl, she dropped her purse. That's when she came in my face, pushed me, and then my glasses came off, and then, like, I had, like, jumped at her, like, to watch out."
"And then she came in my face. I put my head down. And she swung on me."
"I was so shocked, because she hit me so hard. It felt like a dude hit me. And after that, like, my face went boom, my reaction was just right there."