Playing the black side of a Sicilian Najdorf, Sethuraman capitalized on his chances in the middle game and launched a direct attack on the king that resulted in his winning a piece for a couple of pawns. Stukopin hung in there trying to find some counter play but the Indian came up with a startling manoeuvre to force checkmate after a knight sacrifice.
Grover was at his technical best in another Sicilian Najdorf of the day and got a passed pawn on the queenside with some precise calculation. Ali was at sea in figuring out the best defense with his clock ticking away and Grover's Queen and Bishop dealt the knockout blow.
Debashish Das and Vidit Gujrathi also moved to four points in contrasting styles. Das again came up with a fine positional display and defeated Martin Romero Martinez of Colombia while Gujrathi played out a draw with Polish Duda Jan-Krzysztof.
In the girls' championship being held simultaneously, G K Monnisha lost to Meri Arabidze of Georgia. But, Rucha Pujari brought cheers to the Indian camp defeating higher rated Indonesian Monica Sihite Chelsie.
The highest rated Indian, Padmini Rout was held to a draw by Sarasadat Khademalsharieh of Iran. Rucha, Padmini and Monnisha all have an identical 3.5 points from five rounds.