India beat Maldives 1-0 on Monday to make the SAFF Cup final for a record ninth time.
Mondal's maiden international goal will see the defending champions face Afghanistan in final of the SAFF Football Championship on Wednesday.
Mondal, the lad from Kolkata's Behala region, was a bundle of nerves throughout the match but turned out to be an unlikely hero in the end with a delightful strike.
The winner came in the 86th minute when Mehtab Hossain's corner from the right flank was neatly headed down by Syed Rahim Nabi and Mondal, who had joined the attack, struck a powerful angular right-footer that crashed into the net.
There was post-match drama with some ugly scenes as Maldives substitute Ali Umar attacked referee Idham Mohammed and was red-carded after the match. But it did not stop there. A group of Maldives players attacked one of the organisers, and police personnel were called to intervene as things seemed to get out of hand.
According to reports, Birat Jung Shahi, Nepal FA treasurer, was also beaten up by the Maldives players.
However, the match saw India put up an improved performance. Maldives' striker Ali Ashfaq was tied down for most part of the match with India employing zonal marking with makeshift captain Gourmangi Singh giving a good account of himself.
Maldives created a bit of pressure from set-piece movements giving some anxious moments to Indian custodian Subrata Paul.
In the second minute, Maldives got a free-kick and Mohammed Sifan's low delivery which evaded the wall saw Paul fumble trying to gather it on the bounce but forward Mohammed Umair's shot went straight to the goalie.
Another anxious moment came in the 27th minute when Ashfaq's left-footed inswinging free-kick was nicely parried away by Paul.
It was a goalless first half but India played with some intent unlike their horrible show against Nepal. Jeje Lalpeklhua, operating from wide left, tried to make inroads while Arata Izumi, in central midfield, worked tirelessly helping in build ups and acting as a snatcher also.
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