As has been the norm recently, Bagan took an early lead when Komron Tursunov was adjudged to have been tripped inside the box by Dhanchandra Meetei. Gonzalez converted the resultant penalty with consummate ease.
Mohun Bagan were reduced to 10 players after captain Dhanachandra Singh was sent off for handling a goal-bound ball at the one-hour mark.
The deadlock was broken in the 24th minute when Gokulam keeper Ubaid CK brought down Ashutosh Mehra inside the box and referee Crystal John pointed to the spot to award a penalty to Mohun Bagan.
