[Event "Weak Squares: Opera House Game"] [Date "2024.10.13"] [Result "*"] [Variant "Standard"] [ECO "C41"] [Opening "Philidor Defense"] [StudyName "Weak Squares"] [ChapterName "Opera House Game"] [ChapterURL "https://lichess.org/study/o8rkCdB0/ZB2EBEOY"] [Annotator "https://lichess.org/@/Kyle-and-Jess"] [UTCDate "2024.10.13"] [UTCTime "23:41:32"] [Orientation "white"] 1. e4 e5 2. Nf3 d6 3. d4 Bg4 4. dxe5 Bxf3 5. Qxf3 dxe5 6. Bc4 { Pressuring the weakness on f7 (and activating the light-squared bishop to further push the weakness of the light squares). } 6... Nf6 { Blocking the attack but not actually supporting f7 at all. } (6... Qf6 { Better is to offer the trade of queens (which white should reject if playing for a win) and add actual defense to f7, making it less weak in the long run. }) 7. Qb3 { Shifting the queen to the queenside allows for further pressure on f7 and now we're also pressuring b7 (punishing black for trading their light-squared bishop so early). } 7... Qe7 8. Nc3 { Targeting weak light squares (b5 and d5) and stopping Qb4+ (if they still play that (without it giving check), we can just take on f7). } (8. Qxb7 Qb4+ { Taking the pawn allows black to force the trade of queens. Morphy didn't want this (he wanted to keep his queen so he could continue attacking, not just win a pawn and call it there). }) 8... c6 { Controlling the light squares. The queenside pawns are the only things holding the light squares together on the queenside. } 9. Bg5 { Developing the last piece and pinning black's only developed piece. } 9... b5?? { Although this at first seems like a good way to push white back, black is in no position to attack. The queenside pawns were the only things holding the weak light squares together and now they're vulnerable. } 10. Nxb5! { The bishop and the queen are too important for the attack, so we sac the knight! } 10... cxb5 11. Bxb5+ { Now the light squares are wide open on the queenside. } 11... Nbd7 { d7 is now a weak square, pinned to the king and barely defended (although it seems defended by the queen and king (two pieces too valuable to be left to defend a knight) and the knight (which is pinned)) } 12. O-O-O { Targeting the weak d7 square. } 12... Rd8 13. Rxd7 { Trading which piece stands on the weak square. This is white's fastest way to bring in the final rook with pressure on the current weakness. } 13... Rxd7 14. Rd1 { Pressuring the weakness. } 14... Qe6 { The weak square has just shifted now that the queen has moved. It's hard to understand why just yet, but our new weakness lies on the h4-d8 diagonal. The d8 square is targeted twice (by the d1 rook and the g5 bishop) and if we can open both of those pieces toward the d8 square, we'll have the chance for Rd8#. So white starts to devise a plan to open those lines. } 15. Bxd7+ { Forcing the queen to give itself up. If the knight takes, the bishop's line to d8 is open and the square becomes more vulnerable. That's exactly what happened in the game. } 15... Nxd7 16. Qb8+ { Now the knight is forced to take and open the rook as well. Checkmate will follow. } 16... Nxb8 17. Rd8# *