In the summer of 1957, both the New York Giants and the Brooklyn Dodgers announced their moves to California

1. Initially, "play it by ear" referred to the playing of music without reference to printed notation. More recently it is also used figuratively to mean 'handle a situation in an impromptu manner', i.e. without reference to pre-determined rules or guidelines.
2. In the summer of 1957, both the New York Giants and the Brooklyn Dodgers announced their moves to California to become the San Francisco Giants and Los Angeles Dodgers.