ATK Mohun Bagan held their nerves in a tightly contested Indian Super League final to beat Bengaluru FC 4-3 on penalties and lift their maiden title here on Saturday.

In a game that ended 2-2 in regulation time, ATKMB's Dimitri Petratos scored all three penalties he took on the night before Vishal Kaith's save from Bruno Ramires' in the shootout brought them one step closer.

Bengaluru FC's Pablo Perez then sent his spot-kick over the bar as the Mariners sealed the result in a game where they had unsettled Bengaluru FC right from the start.

Bengaluru FC were forced into bringing Sunil Chhetri early on after Sivasakthi Narayanan was stretchered off in the opening seconds of the match.

Things went further away from plan in the 13th minute when Krishna handled the ball from a Petratos corner as ATKMB were awarded a penalty. Petratos finished the job from the spot to put his team in front.

ATKMB made use of this advantage to put pressure on Bengaluru FC, who picked up a glut of yellow cards on the pitch and one off it for head coach Simon Grayson.

But in the final minute of first-half stoppage time, they were given a way back when Bose missed the ball and made contact with Krishna while attempting a clearance. Chhetri stepped up to take the penalty and sent Kaith the wrong way to restore parity.

In the final quarter of the game, Rohit's shot from the edge of the box created a series of corners, before a deflection found Krishna at the far post, and the striker nodded it home in the 78th minute.

But five minutes from time, the game was all square again. At the edge of the Bengaluru FC box, Kiyan Nassiri went down after a nudge from Perez as ATKMB won their second penalty of the evening. Petratos was on hand to score again.

In the third minute of stoppage time, Asish Rai's goal bound shot was cleared off the line by Prabir Das. Moments later, Colaco and Nassiri almost combined to score, but Bruno Ramires provided the crucial interception as the game went into extra time.

Udanta Singh and Rohit failed to hit the target in their respective attempts in extra time, while Manvir missed from a few yards out for ATKMB.

Towards the end of extra time, Sandhu spilled Petratos' long-range strike, but it bounced out for a corner that led to nothing before the game headed into penalties.

In the nervy penalty shoot-out, Golden Glove winner Kaith stepped up for his team for the second game in a row, while no one missed from the spot in a game dictated by penalties throughout.

As the winners, ATKMB took home a prize money of Rs 6 crore, while runners-up Bengaluru FC received Rs 2.5 crore.