Opera Mate: chess tactic

Rook delivers, bishop guards the king's only escape

A rook (or queen) checks the king along a file or rank; a bishop covers the single flight square. Named after Morphy's 1858 game against the Duke of Brunswick and Count Isouard at the Paris Opera, the cleanest example in the chess canon. The pattern shows up wherever a back-rank king has lost its luft and a long-range piece is aimed at the corner.

• Rook delivers check on the back rank; bishop guards the one escape square.
• The bishop sits diagonally adjacent to the king's flight square.
• Morphy's Opera Game (1858) is the textbook example, well worth a look.
• Look for it any time a king is trapped on the edge with limited support.