Valmiki Ramayana Yuddha Kanda Sarga 73 Shloka 9
Original Shlokaतमास्थायमहातेजारथंहरिरथोपमम् । जगामसहसातत्रयत्रयुद्धमरिन्दमः ।।6.73.9।।
1 source checked for this shloka
महातेजाः highly energetic, अरिन्दमः tamer of enemies, हरिरथोपमम् like that of Indra, रथम् chariot, तम: he, आस्थाय taking seat, यत्र there, युद्धम् battle, तत्र there, सहसा quickly, जगाम went.
Highly energetic he (Indrajith) was, a tamer of enemies, seated in the chariot that was like Indra's, quickly went to the battlefield from there.