Mischa is Sergei's translator in "The One Where Ross And Rachel Take A Break". He was portrayed by Stephen Kearney.
Phoebe is irritated when Mischa follows her and Sergei around on their date when having to translate for Sergei and so she calls Monica to come along and date him to which she accepts.
In a restaurant, Misha and Monica appear to hit it off while Misha soon becomes fed up with Sergei, even telling him "Why don't you learn some English, Sergei?". He resigns his post and takes off with Monica, leaving Phoebe and Sergei alone and unable to communicate.