The former Mohammedan striker wasted a penalty-kick before the break, but made amends late into the second half, with the result heaping more misery on the Black and Whites.
Arthur Papas made three changes to his side that lost against Salgaocar as Clifford Miranda and Simon Colosimo returned from suspensions while Tolgay Ozbey was included in the starting eleven after being allowed to feature against his former side only on the eve of the tie. Selwyn Fenandes, Sanju Pradhan and Roberto Da Silva made way for the trio.
On the other hand, Sanjoy Sen also made three changes from the side that lost 2-1 to East Bengal as he brought back Collin Abranches in place of Monirul Mondal. Sandeep Sangha and Ishfaq Ahmed were part of the line-up replacing the injured duo of Luciano Sobrosa and Syed Rahim Nabi.
The first scoring chance of the game fell to Dempo when Romeo Fernandes attempted a shot from inside the box after Ozbey had misfired, but his left footed strike was pushed away for a corner.
In the 10th minute, a strong penalty appeal from the home side was turned down by referee B. Balasubramaniam, after Tolgay Ozbey went down in the box under a challenge from Sandeep Sangha.
The Australian striker once again invaded the Mohammedan box in the 31st minute, this time from the right side, and dribbled past a couple of defenders before taking a shot, which was saved easily by Luis Barreto.
However, the best chance of the half came to Dempo in the 39th minute as the referee pointed straight to the penalty-spot after an ill-timed tackle from Rakesh Masih brought Ozbey down.
The striker stepped up to take the spot-kick himself but his poor effort was parried away with ease by the custodian. The ball fell to Romeo Fernandes on the rebound, whose effort was forgettable from close range.
Ozbey was once again in the thick of things a couple of minutes later, as he got the better of a number of Mohammedan bodies after getting the ball right outside the box. Despite having plenty of time to shoot, he fired his effort wide.
Mohammedan got their first chance of the match on the brink of the half-time whistle when Penn Orji was fed in a brilliant position inside the Dempo box, but his powerful effort was parried away by Laxmikant Kattimani under the bar.
After the break, Clifford Miranda missed an easy chance in the 62nd minute, after Ozbey sent in a cross.
The deadlock, however, was broken in the 77th minute by Ozbey who unleashed a thunderbolt after getting the ball on rebound after Barretto had saved a brilliant strike by Clifford Miranda.
They had a chance to double their lead when Sanju Pradhan ran past several defenders and passed it for Ozbey who in turn laid it for the onrushing Miranda from the left. The Dempo skipper's shot was way off the mark however.
With this win, Dempo now have 28 points from their 20 games and have grabbed the fifth spot in the table, while Mohammedan have 17 points from their 19 matches and have only Churchill Brothers below them, though it must be noted that the Red Machines have a couple of games in hand.
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