Valmiki Ramayana Kishkindha Kanda Sarga 16 Shloka 26
Original Shlokaततोऽवर्धत वाली तु बलवीर्यसमन्वितः। सूर्यपुत्रो महावीर्यस्सुग्रीवः परिहीयते4.16.26।।
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ततः then, बलवीर्यसमन्वितः endowed with strength and valour, वाली Vali, अवर्धत he grew, महावीर्यः mighty, सूर्यपुत्रः Sun's son, सुग्रीवः Sugriva, परिहीयते becomes weak
In a short while Vali, endowed with great strength, gained the upper hand and Sugriva, son of the Sungod, was losing ground .