Undermining (chess) Undermining (chess) Undermining (also known as removal of the guard, or removing the defender) is a chess tactic in which a defensive piece is captured, leaving one of the opponent's pieces undefended or under-defended. The opponent has the unpalatable choice of recapturing or saving the undefended piece. A possible response is to sacrifice the piece whose defense was undermined before capturing the piece which just took the defender. Kramnik–Topalov in the seventh round of the 2004 Linares chess tournament reached the diagrammed position with White to play. The black knight on a4 is defended only by the black pawn on
Chess piece makes the pieces bottom heavy and do not topple easily (a well-weighted piece should come upright even if bent to 60 degrees off vertical axis). This helps in blitz games as the speed of movement doesn't offer enough time or precision in dropping the pieces onto the intended squares. The length of each side of the squares on the chessboard should be about 1.25–1.3 times the diameter of the base of the king, or . Squares of about are normally well suited for pieces with the kings in the preferred size range. These criteria are from the United States Chess