Answer: "Sally" Tessio (Abe Vigoda)
At the end of the movie, "Sally" Tessio (Abe Vigoda) betrays Michael and tries to set up his assassination by rival mob boss Emilio Barzini (Richard Conte). When Michael and Tom realize this, Tom says, "I always thought it would've been Clemenza, not Tessio." Michael then decides Tessio will be executed, and adds "But I'm gonna wait -- after the baptism. I've decided to be Godfather to Connie's baby." When Tessio realizes his plot has been discovered and he is about to be executed, he makes this request of Tom. When Tessio says this quote, Tom replies "Can't do it, Sally." Intercutting the baptism scene with the gang killings during the movie's climax helped earn "The Godfather" an Oscar nomination in the 1973 Academy Awards for Best Film Editing, but it did not win. It did win three Oscars, including Best Picture. Marlon Brando won Best Actor in a Leading Role, but refused to accept the award. Al Pacino, James Caan, and Robert Duvall were all nominated for Best Actor in a Supporting Role, but none of them won the Oscar.