Mbh 6.19.2a

Sanjaya said,--“Seeing the Dhritarashtra divisions arrayed in order of battle, Pandu’s son of virtuous soul, king Yudhishthira the just, addressed Dhananjaya, saying,--‘Men are informed from the words of that great Rishi Vrihaspati that the few must be made to fight by condensing them, while the many may be extended according to pleasure. In encounters of the few with the many, the array to be formed should be the needle-mouthed one. Our troops compared with the enemy’s are few. Keeping in view this precept of the great Rishi, array our troops, O son of Pandu.’ Hearing this, that son of Pandu answered king Yudhishthira the just, saying,--‘That immovable array known by the name of Vajra, which was designed by the wielder of the thunder-bolt,--that invincible array is the one that I will make for thee, O best of kings. He who is like the bursting tempest, he who is incapable of being borne in battle by the foe, that Bhima the foremost of smiters, will fight at our head. That foremost of men, conversant with all the appliances of battle, becoming our leader, will fight in the van, crushing the energy of the foe. That foremost of smiters, viz., Bhima, beholding whom all the hostile warriors headed by Duryodhana will retreat in panic like smaller animals beholding the lion, all of us, our fears dispelled, will seek his shelter as if he were a wall, like the celestial seeking the shelter of Indra. The man breathes not in the world who would bear to cast his eyes upon that bull among men, Vrikodara of fierce deeds, when he is angry.’--Having said this, Dhananjaya of mighty arms did as he said. And Phalguni, quickly disposing his troops in battle-array, proceeded (against the foe). And the mighty army of the Pandavas beholding the Kuru army move, looked like the full, immovable, and quickly rolling[103] current of Ganga. And Bhimasena, and Dhrishtadyumna endued with great energy, and Nakula, and Sahadeva, and king Dhrishtaketu, became the leaders of that force.