Srimad-Bhagavatam: Canto 10 - Chapter 1 - Verse 26
Sanskrit:
तत: कूटमनुप्राप्तं राम: प्रहरतां वर: । अवधील्लीलया राजन्सावज्ञं वाममुष्टिना ॥ २६ ॥
ITRANS:
tataḥ kūṭam anuprāptaṁrāmaḥ praharatāṁ varaḥavadhīl līlayā rājansāvajñaṁ vāma-muṣṭinā
Translation:
Confronted next by the wrestler Kūṭa, Lord Balarāma, the best of fighters, playfully and nonchalantly killed him with His left fist, O King.