Mohammedan SC dropped crucial points after losing 0-3 to one of their closest rivals, Real Kashmir, in an I-League fixture at the Naihati Stadium in Naihati on Sunday.
The Black Panthers still retain their lead at the top of the table with 27 points to their name but second-placed Kashmir are edging closer towards the Kolkata outfit, having amassed 23 points so far.
The loss adds a bit of anxiety to the Mohammedan camp given that third-placed Sreenidi Deccan beat Churchill Brothers 2-1 away earlier in the day.
The Deccan Warriors are separated from Real Kashmir by a mere goal difference of three.
If Mohammedan continue to lose points this way, they might end up in trouble at the end of the I-League season.
Sreenidi Deccan and Real Kashmir are pushing quite hard to go to the top of the table and in turn, win promotion into the Indian Super League (ISL) next season.
Ivory Coast striker Gnohore Krizo was Real Kashmir's star against Mohammedan
Shaher Shaheen started the scoring for Real Kashmir with a free header in the 55th minute while a brace from Gnohore Krizo sealed the deal for the Snow Leopards.
The crowd in Naihati was left stunned after Krizo doubled his side's lead in the 64th minute before scoring another from the penalty spot in the dying stages of the game.
Andrey Cherneyshev's side will go back to the drawing board and assess what went wrong for them on Sunday.
The Kolkata outfit will try to come back strongly from the loss and hope to keep their lead at the top of the table.
While Mohammedan will travel to Mizoram to take on Aizawl on February 10, Real Kashmir will play Rajasthan United at the Namdhari Stadium a day before that.