What is the story of Nana Chandorkar and the power of faith-infused Udi?

As detailed in Chapter 33, a devotee whose daughter was afflicted with glandular fever sent a message to Nana Chandorkar, pleading for him to pray to Baba and send Udi. When Nana received the message at Thane station, he had no Udi with him. In a profound act of faith, he picked up ordinary clay from the road, offered a prayer to Sai, and at that very moment, the girl's severe fever began to subside in a distant village. This story beautifully illustrates that the healing power was not confined to the physical Udi from Shirdi but was activated by Nana's unwavering faith and prayer, which could transform even a particle of clay into a potent Prasad of Sai.