How did Sai Baba get his name?

The name 'Sai' was given to Baba upon his arrival in Shirdi with a wedding party. Chapter 5 narrates that the procession, including the carts and horses, stopped near Khandoba's temple. As the young Fakir stepped down from one of the carts, he came into the sight of a devotee named Mahalsapati. Mahalsapati instinctively went forward and greeted him with the words 'Ya Sai,' which means 'Welcome, Sai.' The text explicitly states that from that moment on, the name stuck, and people began calling him 'Sai, Sai,' making it his recognized name.