Roy Krishna's 67th-minute strike was enough for Habas' team to secure three points in the club's first-ever ISL match.
It was a cagey start as both teams adopted a safety-first approach. Yet, Bagan could have had their noses in front had Krishna not scuffed his shot at the far post after latching on to a corner whipped in by Hernandez early on in the game.
But they were jolted by an injury to Michael Soosairaj within the first 15 minutes of the match, as the wing-back could not continue following a clumsy challenge from Prasanth Karuthadathkuni.
Minutes later, Blasters' Kone gave away possession cheaply at the back but Krishna could not make them pay. Costa Nhamoinesu did well to block the ATK Mohun Bagan striker's shot which was on target.
The Fijian continued to be involved in every move and once again got an opportunity to put his team in front in the 34th minute. He attempted a strike from the edge of the box but it sailed over the crossbar.
The men in yellow dominated possession but lacked creativity in the attacking third.
Sahal Abdul could have easily been the hero for his side as he found himself in a convenient position to break the deadlock after the restart. Jessel Carneiro crossed from the left flank and the ball fell to Sahal who was inside the box with a lot of space to attempt a shot. The Blasters midfielder failed to convert the chance and failed to hit the target from close range.
The deadlock was finally broken in the 67th minute when Roy Krishna netted the first goal of the season from Manvir Singh's cross. Singh made a run down the left flank and clipped a ball into the box to Krishna who found the back of the net. Two Blasters defender were in the area to clear the ball but their hesitant defending allowed the Bagan forward to pounce.
The home side pushed hard for an equaliser but ATK Mohun Bagan's defensive setup, led by Carl McHugh and Sandesh Jhingan did not allow them space to operate.