Valmiki Ramayana Yuddha Kanda Sarga 59 Shloka 120
Original Shlokaतंसमुत्सृज्यसाशक्तिःसौमित्रिंयुधिदुर्जयम् ।।6.59.120।। रावणस्यरथेतस्मिन् स्थानंपुनरुपागता ।
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साशक्तिः that power, युधि in war, दुर्जयम् vanquish, सौमित्रिम् Saumithri, रावणस्य Ravana's, तस्मिन् रथे in his chariot, पुनः again, स्थानम् position, उपागता returning back.
That power returned back to Ravana's chariot to its position, leaving Lakshmana, who was difficult to vanquish.