Mohun Bagan bounced back from one goal deficit to register a nail-biting 2-1 win over Air India and set up a semi-final derby against arch-rivals East Bengal in the 30th Federation Cup at the floodlit Vidyasagar Krirangan in Barasat on Tuesday.

The three points from the win took Bagan's tally to six and share the top spot of Group C with Vasco SC with same goal difference (one).

However, on account of the goal scored -- four for Bagan and three for Vasco -- as per the new rules, the green-and-maroon brigade advanced to the last-four stage.

After given the lead by Soccor Velho in the first-half, Bagan equalised through Lal Kamal Bhowmick before a penalty conversion by Marcos Pereira settled the issue for the green-and-maroon brigade.

On a day when Brazilian ace Jose Ramirez Barreto was missing his silken touch and Indian captain Bhaichung Bhutia becoming unlucky with his headers, it was substitute Bhowmick who set the ball rolling for the 12 times Fed Cup champions. 

Having begun with a half-an-hour delay with the Bimal Ghosh and Co stuck in Kolkata traffic snarl-up, Air India were halted in the field also especially after they got a brilliant start thanks to some goodwork by the unassuming Velho. 

Taking opportunity of  Bagan's mid-field and defensive lapses which gave Karim Bencherifa a torrid time in the first-half, Air India drew first blood in the 26th minute.

Having snatched the possession from Bagan's Pereira, Surojit Roy brilliantly passed it to a surging Velho who launched a streaming attack into the opponent's net to give the Mumbai side lead.

Bagan custodian Sangram Mukherjee, however, did well to recover as he thwarted a fine freekick from Samson Singh to keep their hopes alive.

After the changeover, Bencherifa replaced Shylo Malswam Tulunga, who missed a couple of chances in the first-half, with Bhowmick that turned out to be the golden move of the day.

Adding the much-required spunk to mid-field, Bhowmick presence clearly made the difference as he scored seven minutes after the break from a Pereira pass.

A minute later, Bhowmick set it up for Barreto but the Brazilian was visibly not in his best today with his left-footer missing the target.

But the Brazlian played a role in Bagan's winner. In the 58th minute, Barreto was brought down at the edge of the box by Haobijam Napoleon Singh and the freekick was scintillatingly converted by an angling Pereira strike which handed Mohun Bagan a place in the semi-final.

The excitement, however, did not cease there with more drama unfolding for Air India who were awarded a penalty after assistant referee A Arjunan spotted a handball by Bagan defender Joseph Anandavasan in the 72nd minute.

Youngster Ravinder Singh converted the penalty, but only to be fouled by referee T Pradeep Kumar in a dramatic fashion. 

Bagan goalkeeper Sangram Mukherjee, however, did falter as Ravinder missed in his second attempt. In fact, Sangram saved another freekick towards the fag-end, as Bagan ensured the last-four berth.

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