Valmiki Ramayana Yuddha Kanda Sarga 76 Shloka 86

ततः then, कुम्भः Kumbha, समुत्पत्य rising up, सुग्रीवम् Sugriva, अभिपद्य च hit him, क्रुद्धः in anger, वज्रवेगेन at thunderbolt speed, मुष्टिना with fist, उरसि on the chest, आजघान struck.

Then Kumbha hit Sugriva in anger with his fist at the speed of a thunderbolt on his chest.