Porn Star Christy Mack -- Free Facial Reconstruction

Christy Mack faces a long road to recovery after being viciously beaten ... allegedly by War Machine ... but a Bev HIlls plastic surgeon has come to the rescue.

Dr. Harrison H. Lee has reached out to Mack ... offering facial reconstructive work for free. Dr. Lee says he feels a special responsibility because he's trained in mixed martial arts and knows it should never be abused.

It's unclear if Mack is down with the offer ... but it sounds like a good deal.

As TMZ previously reported, Mack's porn star friends have been raising money on her behalf ... nearly $65,000 so far on GiveForward.com.