The first game of the first-round match, won by Anderssen with the Black pieces. Kieseritzky's twentieth move — throwing away the only guard of his king — drew from Staunton one of his most memorable rebukes.
19…Rf6The intention of Black in making this move was, unmistakeably, to play the R. afterwards to K. R's 3rd and attack the Q. It is on this account that the reply of White is so utterly inexplicable.
20.Rg3The annals of Chess will be searched in vain for so extraordinary a proof as this game affords of the influence nervous excitement may have upon the Chess powers. Instances are not rare, indeed, where, in a match of importance, players, even as excellent as Mr. Kieseritzky, have overlooked an obvious mate, or, what may have been tantamount, the loss of their Queen; but, in this case, with the warning move of R. to K. B's 3rd, which Black had just made, to play away the only Piece which guards him from checkmate, and to move that in such a manner that the adversary may win his Queen, is a sort of double-barrelled blunder I have hardly ever seen equalled, even among beginners at the game.
Howard Staunton, The Chess Tournament (1852) · Public domain · source