Biography: Mitchell Whitfield (born on September 8, 1964) is an American actor. He may be best known for his role as Stan Rothenstein, opposite Ralph Macchio, in My Cousin Vinny. He guest-starred in several episodes of Friends as Dr. Barry Farber, Rachel's orthodontist ex-fiancé whom Rachel left at the altar on their wedding day. He also appeared in Dharma & Greg; Murder, She Wrote; Diagnosis Murder and CSI: Crime Scene Investigation. He voiced Phobos on W.I.T.C.H. and Donatello in the 2007 TMNT film. From Wikipedia, the free encyclopedia.