However, the Kolkata side is still atop the league standings with 12 points.
The Pune franchise, who travelled without their French World Cup winner David Trezeguet, stunned one and all Dudu, their East Bengal recruit, repaid his coach's faith in him with a well-directed header in the 31st minute to silence the crowd.
Till then, Atletico Kolkata, who were bolstered by the return of mercurial forward Fikru Teferra and manager Antonio Habas, off the field, impressed with their passing and had a better share of possession against a Pune defence that looked weak.
But the day clearly did not belong to the league leaders, who had two howlers early on with their top two striking duo -- Fikru and Borja Fernandez -- missing one each.
Having seized the momentum thanks to the Nigerian's strike, Kostas Katsouranis made it 2-0 after the break. The Greek World Cupper used his out-step to curl one away as goalkeeper Subhasish Roy Chowdhury watched the ball enter the net in disbelief.
Kolkata made their presence on the score-sheet in the
84th minute after Pune goalkeeper Arindam Bhattacharya brought down Fikru and the Ethiopian converted from the spot without much fuss.
Pune then got a free-kick at the edge of the box when Josemi pushed Dudu from behind and Davide Colomba’s left-footer took a deflection off Kingshuk Debnath to hit the back of the net.
Image: Atletico de Kolkata (white) and FC Pune City players in action during their ISL match in Kolkata on Friday.
Photograph: PTI
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