The Pandava army became so by virtue of the prowess of your son. Seeing, O Bharata, that the Pandava army was being destroyed by your son.
बभूव पाण्डवी सेना तव पुत्रस्य तेजसा। पाण्डुसेनां हतां दृष्ट्वा तव पुत्रेण भारत॥