CC Ādi 14.3
yaśodā-nandana yaiche haila śacī-putra
I have thus described in brief the advent of Śrī Caitanya Mahāprabhu, who appeared as the son of mother Śacī exactly as Kṛṣṇa appeared as the son of mother Yaśodā.
Śrīla Narottama dāsa Ṭhākura confirms this statement that now Lord Kṛṣṇa, the son of mother Yaśodā, has appeared again as Lord Caitanya Mahāprabhu, becoming the son of mother Śacī:
balarāma ha-ila nitāi
“The son of Śacī is none other than the son of mother Yaśodā and Nanda Mahārāja, and Nityānanda Prabhu is the same Balarāma.”