 Originally it was to be Clemenza who agrees to testify against the  Corleones. However, Richard S. Castellano (qv) (who was the  highest paid actor in _Godfather, The (1972)_ (qv)) wanted to write  his own lines and wanted a large salary increase. Consequently his  character was replaced by Frankie Pentangeli  (Michael V. Gazzo (qv)) who received an Oscar nomination for the  performance.