Caitanya-caritāmṛta 20.307
Blended reading (Sanskrit + English inline)
This is a description of the Rudra form, which is another expansion of Kṛṣṇa. Only viṣṇu-mūrtis are expansions of Kṛṣṇa’s personal and plenary portions. Mahā-Viṣṇu, who lies on the Causal Ocean, is an expansion of Saṅkarṣaṇa. When Garbhodakaśāyī Viṣṇu accepts the material modes of nature for the purpose of dissolving the cosmic manifestation, His form is called Rudra. As already explained, Lord Viṣṇu is the controller of māyā. How, then, can He associate with māyā? The conclusion is that the incarnation of Lord Śiva or Lord Brahmā indicates the absence of the supreme power of Viṣṇu. When the supreme power is not there, it is possible to associate with māyā, the external energy. Lord Brahmā and Lord Śiva are to be considered creations of māyā.
My note
Source: vedabase.io