The way I heard it Rick Danko sent a tape of his band to Mary Martin. She thought they would be good for Bob Dylan and passed the tape along to him. Dylan didn't go for them, but Martin persisted. She ultimately set up a face to face with Dylan, Robbie Robertson and Levon Helm. Dylan liked them and offered the two a place in his band, but Helm insisted that he had to take the whole group. Dylan relented and the rest is pop music history.
Talent can only get you so far. Artist need somebody to champion them. Someone to tell people that you got to hear so and so. Think Jimi Hendrix and Chas Chandler or even Elvis and Colonel Parker. Mary Martin was one of the best at her job.