Here's how the two teams lined up:
KBFC: Albino Gomes, Costa, Kone, Jessel, Cidoncha (C), Vicente Gomez, Prasanth K, Ritwik, Sahal, Naorem, Hooper
ATKMB: Arindam, Kotal (C), Jhingan, Tiri, Prabir, McHugh, Pronay, Javi, Soosai, Krishna, Edu Garcia
The first half was a cagey affair and remained goalless, with ATKMB failing to convert their chances. Kerala dominated possession but lacked the end product in the final third.
It was Kerala who started brightly, intent on keeping the ball while Kolkata side were keen on absorbing the pressure.
The Mariners had the chance to take the lead off what was the first corner of the game, with the ball falling to an unmarked Krishna. The Fijian though failed to get the desired connection and scuffed it out for a goal-kick.
ATKMB were forced to make their first substitution in the 15th-minute when Michael Soosairaj was stretchered off the field after being fouled by Prasanth Karuthadathkuni. He was replaced by Subhasish Bose.
Bagan had the opportunity to put themselves ahead, through a corner again soon. Edu Garcia found Carl McHugh but the Irishman fired his header wide. Krishna had another great chance soon after the half-hour mark, with the ball falling to him after a mistake by Vicente Gomez. However, the Fijian blazed his shot over the bar.
Shortly after that, Kerala had their best chance of the game. Nongdamba Naorem whipped in a cross from the left but a block from McHugh lobbed off towards the centre of the box. An onrushing Ritwik Das, however, missed the target from close distance.
Vicuna's men continued to dominate possession in the second half and their efforts led to a clear-cut opportunity. Carneiro burst forward and crossed the ball to Sahal Abdul Samad, who miscued his shot.
The deadlock was finally broken in the 67th minute due to a mistake by the Kerala defence. Sergio Cidoncha and Jose Vicente Gomez made a mess of clearing Manvir Singh's lobbed ball and succeeded only in diverting it into Krishna's path. The Fijian made no mistake, scoring Bagan's first goal of their ISL sojourn.
Kerala pushed hard for an equaliser, bringing on Puitea and Jordan Murray, but were eventually let down by their poor finishing.