In post-Vedānta Deśika (traditional dates 1269-1370) Viśiṣṭādvaita Vedānta texts Hayagrīva seems to have assumed the function Gaṇeśa has in all other texts, namely he is invoked at the beginning as the God of learning, protecting the intellectual enterprise one is about to undertake.

(Musée Guimet, Cambodia)

More prominent than in Gaṇeśa is, however, his role as a teacher, so that he is often found in invocations together with one’s teachers, e.g.,

śrīmate hayavadanaparabrahmaṇe namaḥ |
śrīmate bhagavadrāmānujāya namaḥ |
śrīmate nigamāntamahādeśikāya [=vedāntadeśikāya] namaḥ |

“Honour to Hayagrīva!
Honour to Rāmānuja!
Honour to Vedānta Deśika!”

In other cases, the invocation assumes further elements, but the intellectual role of Hayagrīva is always in the foreground, e.g.,

nirmatsarā niśamayantv idam ādareṇa karmādhikāranayasūtragatiṃ samīcīm |

śārīrakeṇa ghaṭayaty ayam asmaduktyā devas turaṅgavadano jagadantarātmā ||

“ [This] correct path through the aphorisms about the rules regarding the ritual action (i.e., the Pūrvamīmāṃsāsūtra), this one God, horse-faced (i.e., Hayagrīva) and inner self of the world, he unites it with the Śārīraka (i.e., the Vedāntasūtra) by means of my voice”

(beginning of Vedānta Deśika’s Seśvaramīmāṃsā)

References to Hayagrīva’s myth and to the way he rescued the Vedas from one or two asuras are more rare and I found them only in later maṅgalas, e.g.,

vandeya śrīhayāsyāṃ vidhihitavidhaye naṣṭavedopadiṣṭaye labdhāvirbhāvam ādau suramunivinutaṃ sarvavidyādhidevam |

“I should salute at the beginning the venerable Hayagrīva, the tutelary deity of all knowledge, praised as the celestial sage, who managed to manifest [back] [the Vedas] for the sake of prescribing the fruitful which is in the [Vedic] prescriptions [and] for the sake of teaching the Vedas which had been destroyed [by the Asura]”

(beginning of the Satpathasañcāra commentary on Vedānta Deśika’s Mīmāṃsāpādukā)

Or:

śrīmān vājimukhaḥ śriyaṃ vitanutāṃ yenopadiṣṭo ‘khilo vedaḥ svātmabhuve ‘rpitaś ca punar apy āhṛtya hatvāsurau |
yasyāṃśaḥ sahajaiminir munivaro vyāsaḥ sa pārāśarimīmāṃsāṃ niramāt sakarmabhagavadjñaptyai vimuktipriyaḥ || 1 ||

The exalted Hayagrīva , through which the whole Veda has been taught, the Veda which has been transferred on the earth —which is his own self— after he had taken it back and killed the two asuras, may he spread splendor [upon us]!*

(beginning of the Sūkṣmārthaṭīkā on the SM)

Did you ever encounter Hayagrīva in similar situations? Connected with learning and the Vedas? Or with a determinate tradition?

*Many thanks to Gianni Pellegrini for a useful suggestion concerning this verse.