John Daly -- Mouth Tee Off Shot '100% Real' ... Says Woman In Video

The shocking video of John Daly hitting a golf ball off a tee that's firmly placed in a woman's mouth is "100% REAL" ... at least that's what the woman in the footage tells TMZ Sports.

We spoke to Katherine Michelle -- who happens to be a model -- and she tells us the whole thing went down on August 10th in Augusta, GA.

"J.D. has loads of talent and he's one of my best friends. I trust him with my life," Michelle says ... noting, "His girl is also my best friend."

Michelle says she did know about the famous Playboy golf shot gone wrong -- where a model was injured when she let a DJ hit a ball off of a tee in her butt -- but clearly, it didn't dissuade her.

When asked if she was ever worried about something going wrong, Michelle told us "No, because he's done this a few times. He would never do anything to hurt me or others."

Please ... kids ... don't try this at home.