SB 10.26.17

prāgayaṁ vasudevasya
 kvacij jātas tavātmajaḥ
vāsudeva iti śrīmān
 abhijñāḥ sampracakṣate
Synonyms: 
prāk — before; ayam — this child; vasudevasya — of Vasudeva; kvacit — sometimes; jātaḥ — was born; tava — your; ātmajaḥ — Kṛṣṇa, who has taken birth as your child; vāsudevaḥ — therefore He may be given the name Vāsudeva; iti — thus; śrīmān — very beautiful; abhijñāḥ — those who are learned; sampracakṣate — also say that Kṛṣṇa is Vāsudeva.
Translation: 
For many reasons, this beautiful son of yours sometimes appeared previously as the son of Vasudeva. Therefore, those who are learned sometimes call this child Vāsudeva.