Baba announced at the age of 14, that He was Sai Baba who belonged to the Bharathwaja Gothra. Three years ago , when He most dramatically threw off the paralysis of a devotee which He had taken over, He announced that He was 'Siva-Sakthi' come in human form, in response to a boon granted to Bharadwaja Rishi by Siva in the past. Siva had blessed the Rishi that He would take human form in his Gothra (religious kin-group).
Bharadwaja was a great Saint who did penance and won three terms of life of a hundred years each, so that he may master the Vedas. But the God of Gods, Indra, told him that the Vedas are beyond even ages of study and Indra taught him a Yaga instead. For the Yaga, Bharadwaja invited Siva and Shakti as presiding dieties. He won their favour so much that they condescended to be born in the Bharadwaja Gothra (spiritual class) as Sai Baba of Shirdi and as Sathya Sai Baba. He will be born in the same Gothra as Prema Sai Baba in future.
Bharadwaja's Ashram was at Prayag; He is mentioned in the Ramayana as a sage with amazing miraculous powers, won by thapas. Baba declared that He was not Sathyanarayana Raju as people knew Him till then; that was only a make-believe, worn by Him until the world could grasp the news of His divinity. Even His claim to the Gothra of Bharadwaja is a make-believe, for how can the Divine be bound by lineage and kin?