Gloria Allred can add another high-profile case to her resume ... 'cause TMZ Sports has learned the famed attorney has been hired by the girl at the center of the investigation into OKC star Josh Giddey as cops work to determine if he had an inappropriate relationship with a minor.
We broke the story earlier in the week ... Newport Beach PD launched an investigation into the situation, but the girl and her family are not cooperating with law enforcement.