What is the story behind how Maharaj came to be called 'Sai Baba'?

The name 'Sai Baba' was bestowed upon Maharaj by Mhalasapati. As explained in Chapter 0, when Maharaj, dressed in a kafni, cap, and dhoti, entered the Khandoba temple in Shirdi, Mhalasapati spontaneously greeted him with the words 'Aavo Sai Baba,' which means 'Come, Sai Baba.' Maharaj held onto this name for the rest of his life. The text even notes that when his testimony was required in a commission and he was asked his name, he simply replied, 'They call me Sai Baba,' confirming the name's origin from that first meeting.