In the Sinquefield 2015 tournament, Nakamura scored a brilliant win by mating Wesley So in 39 moves. The game was a Queens-Gruenfield where So dominated the Queenside and Nakamura operated in the Kingside. Hell broke lose when Nakamura sacrificed the g and f pawns to clear the King obstacles and offered Knight, Rook, Bishop sacrifices. Then So's King began a march towards Nakamura's territory alone until it got checkmated in g6 square a few moves later.
I thought that checkmate is only for amateurs, but this actually happened even with top caliber grandmasters. So could have resigned early to avoid the humiliation of being mated. But maybe, he choose it to make this a complete immortal game.
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