Cleveland Cavs player Kevin Porter Jr. allegedly punched a woman in the face and ripped out her weave during an altercation back in August ... but Porter's attorney says the claim is bogus.
The allegations are spelled out in police reports obtained by Cleveland.com ... which detail an August 16 incident involving Porter, his sister and two other women.
Porter's sister reportedly "exchanged words" with one of the other women at an apartment complex in Downtown Cleveland and things escalated from there.
Porter's sister allegedly struck one of the women -- and that's when Kevin allegedly jumped in and went after the other woman, a 19-year-old.