Any high-level GM games where somebody makes a big blunder but was in blissful ignorance about how bad the move was until several moves after the blunder?
EDIT thanks to comment: classical time format, not blitz (where blunders are common)
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Sign up to join this communityAny high-level GM games where somebody makes a big blunder but was in blissful ignorance about how bad the move was until several moves after the blunder?
EDIT thanks to comment: classical time format, not blitz (where blunders are common)
Of course this has happened, but it depends on your definitions. With the definition that "a blunder is a move that changes the game-theoretic state of the game" (e.g. "draw" to "loss" or "win" to "draw"), then here's an example where both Ding Liren and Alexander Grischuk were blissfully unaware of the blunder until after the end of the game.
[FEN ""]
[White "Grischuk, Alexander"]
[WhiteElo "2759"]
[Black "Ding, Liren"]
[BlackElo "2811"]
[Result "1/2-1/2"]
[startply "26"]
1. d4 Nf6
2. c4 e6
3. Nf3 d5
4. g3 dxc4
5. Bg2 a6
6. O-O Nc6
7. e3 Rb8
8. Nfd2 e5
9. Bxc6+ bxc6
10. dxe5 Ng4
11. Nxc4 Be6
12. Qe2 h5
13. Rd1 Qc8
14. Qf3? Bd5
15. Rxd5 cxd5
16. Qxd5 Qf5! {Black threatens ...Qxf2+ and mate.}
17. f3! {Both Grischuk and Ding Liren saw this far and could not see a refutation of this move.} Qc2! {Black threatens ...Qxc1+, and ...Qf2+ followed by mate.}
18. Qc6+! {18.Nbd2? Qd1+ 19. Kg2 Qe2+ wins. White has to move the Queen so that the d2-knight is no longer pinned, and Nf1 becomes possible.} Kd8
19. Nbd2 Qd1+
20. Nf1 Nxh2! {20...Rh6? 21. Qe4 Nxh2? 22. Qh4+ and Qxh2 wins for White.}
21. Kxh2 Rh6!! {And Black wins because of the dual threats of ...Rxc6 and ...Qxf1. Comparatively 21...Qxf1? leads 22. e6 when White has enough counterplay to force a draw.}
Grischuk (White) went 14. Qf3? allowing Ding a game-winning continuation beginning with 14...Bd5, that was however not easy to spot by an unassisted human. After seven minutes Ding played ("blundered") 14...Rb6 and the game was eventually drawn.
However: given the complexity of the variation and how hard it is for a human to spot, can you fairly call 14. Qf3 or 14...Rb6 blunders?