SB 10.11.49

kṛṣṇaṁ mahā-baka-grastaṁ
 dṛṣṭvā rāmādayo ’rbhakāḥ
babhūvur indriyāṇīva
 vinā prāṇaṁ vicetasaḥ
Word for word: 
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.
Translation: 
When Balarāma and the other boys saw that Kṛṣṇa had been devoured by the gigantic duck, they became almost unconscious, like senses without life.
Purport: 

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.