GM Al Rakib Abdulla of Bangladesh adopted Nimzo Indian defence against GM Vidit and the game went on expected lines until move 19.
When Vidit doubled his rooks on the open b-file, Abdulla exchanged one of the rooks to minimise Vidit's attack.
But, Vidit made a stunning rook sacrifice on the 23rd move, leading to a knight fork of Abdulla's king and queen as the Bangladeshi GM resigned immediately.
The second board game between Pantsulaia Levan of Georgia and Ziaur Rahman of Bangladesh also ended with a similar result, but it lasted 44 moves.
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