Dakota Stone, the boxer who defeated Christy Martin, thinks she whupped Christy fair and square -- and no matter what Gloria Allred says in a news conference ... the proof is on tape for everyone to see.

Dakota's manager Mathis Hill tells TMZ -- Christy was the crowd favorite, but not the clear winner -- and adds, "The ref only called the fight because Christy turned her back and ran from the fight to go to a neutral corner."

As for Christy and Gloria's news conference this morning ... calling the ref's decision to stop the fight sexist ... Mathis says "the whole thing is a bunch of bull."

Watch the fight clip below -- decide for yourselves.