Why was Arjuna defeated and fled from encounter with valiant robbers in Mahabharata?

Why was Arjuna defeated and fled from encounter with valiant robbers in Mahabharata? Shiva and Indra already answered this Query. Jayadratha asked boon from Shiva to defeat Arjuna. This was Shiva's Reply. Arjuna is protected by Krishna the possessor of these attributes. That glorious and lotus-eyed Being of infinite power, that slayer of hostile heroes, riding in the same chariot with Pritha's son, protecteth him! He is, therefore, invincible; the very gods cannot resist his power, still less can one with human attributes vanquish the son of Pritha in battle! Indra said these words before giving his Celestial spear to Karna. You kill one roaring and powerful enemy in battle. But the one you seek to kill is protected by a great-souled one who is known as the unvanquished boar, Hari and the inconceivable Narayana by those who are learned in the Vedas.” Note:— Krishna doesn't need to Be with Arjuna to protect him. In Virat war , Krishna Used his illusions to Prevent Karna From using Indra's Spear on Arjuna. In this Case Krishna Was No longer There For Protection. So Arjuna was Helpless Against Robbers and accepted it as Destiny and Fled. The other Possible reasons is Arjun's Immense grief due to Krishna's Death. And finally, what's Ordained By Destiny cannot be Defied even By Mighty Arjuna