Michael Gerard Hagerty (born May 10, 1954), also known by his stage name Mike Hagerty, is an American actor. He is known for playing comedic blue-collar workers, including his recurring roles as a building superintendent, Mr. Treeger on Friends, and the manager of a muffler shop on HBO's Lucky Louie.Hagerty is recognized for his small character roles in a wide range of popular comedies, including Cheers, The Wayans Bros., Curb Your Enthusiasm, Friends, Seinfeld, and The Wonder Years.