Sabeeth Sathyan scored for Mohun Bagan but their lead was cancelled out by Sunil Chhetri in the second half to ensure that their last remaining challengers, Pune FC, could no longer catch-up with them.
The Goan side claimed their maiden honour under Serbian coach Zoran Djodjevic in the season 2008-09.
Meanwhile, Churchill Brothers' technical director Subhash Bhowmick has guided a team to the top of the standing after a gap of nine years, following his back-to-back success with East Bengal in the campaigns of 2002-03 and 03-04.
However, the sides trailing the Red Machines, East Bengal and Pune FC, are still in a fight for the runners-up tag, while Prayag United have a possible chance of finishing third in the league.
Churchill Brothers finish their campaign off next weekend, with a trip to Pune where they will face Air India.
|Detailed I-League standings|
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