kṛṣṇaṁ mahā-baka-grastaṁ
dṛṣṭvā rāmādayo 'rbhakāḥ
babhūvur indriyāṇīva
vinā prāṇaṁ vicetasaḥ
kṛṣṇam - unto Kṛṣṇa; mahā-baka-grastam - swallowed by the great duck; dṛṣṭvā - seeing this incident; rāma-ādayaḥ arbhakāḥ - all the other boys, headed by Balarāma; babhūvuḥ - became overwhelmed; indriyāṇi - senses; iva - like; vinā - without; prāṇam - life; vicetasaḥ - very much bewildered, almost unconscious.
Although Balarāma can do everything, because of intense affection for His brother He was momentarily bewildered. A similar thing is stated to have happened in connection with rukmiṇī-haraṇa, the kidnapping of Rukmiṇī. When Kṛṣṇa, after kidnapping Rukmiṇī, was attacked by all the kings, Rukmiṇī was momentarily bewildered, until the Lord took the proper steps.