Chennai City FC slumped to their second defeat of the tournament and find themselves at the bottom of the table.
Robin scored in the added time of the first half and in the 76th minute to guide East Bengal to a hard-earned win.
East Bengal pressed for an early goal and almost took the lead in the sixth minute when Narayan Das' header was cleared off the lines after Karanjit Singh had come out of the line to punch clear a dangerous cross.
The Red-and-Gold brigade turned on the style and piled pressure on the Chennai defence line, courtesy of attacks led by Robin from the front and Wedson Anselme from the wing.
Also Read
Chennai recouped from soaking pressure and with Soundarajan's team committing in midfield, East Bengal were kept at bay.
Entwined in a battle of possession, with neither side dominating the match, it took a mistake from Chennai City FC to open the goal gates.
Robin capitalised on a sloppy clearance from the Chennai City FC defence and scored from inside the box to give East Bengal the lead going into half-time.
Clear goal-scoring chances became rare for both teams as both sides trod with caution. The play became largely confined to the midfield.
In the 72nd minute, Karanjit made a save to deny Robin's header from close range.
The second goal for East Bengal came in the 76th minute when Robin converted from the spot after Ravanan's handball inside the box.
Disclaimer: No Business Standard Journalist was involved in creation of this content