|PawnSac: < OrangeTulip: Gustafson must have seen far ahead when he played 13.Nxe6. Audacious combination. >|
[ 13. _?_ ]
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Stockfish evaluates 13.a3! as much stronger than 13.Nxd6!?
The complete lines are given below, but it runs like this...
13.a3 (threat = 14.b4 fork)
..Qc7 (forced, the only square available!)
14.Rc1! (strong move adding pressure to the pin on c6 while also targeting the Nc5. White still threatens b4 driving the Nc5 away and overloading the pin.)
13...h6 ( black would prefer another square for the Q, like maybe d8,
since on c7 the Rc1 pins against the Q while the Bc5 pins against the K! A very crippling double pin.)
15.Be3 (adding pressure to c5)
15..a6 (desperate to break the pin, but the defense is not adequate.)
16.Bxc6+ bxc6 17.b4 ..and so on.
Actually, Gustafson did not have to see far ahead when he played 13.Nxe6 . It's a very typical "human" move that is positionally motivated and justified. The d5 pawn is very weak. If black recaptures with f7xe6 then as seen in the game the backward e6 pawn is then very weak and lines are opened for a direct assault on the K. The goal is to expose the K, prevent castling, and nail the black monarch down in the center of the board! This is a routine type of strategy.
Notice also that in the Stockfish line black plays ..Nxe6 and gives up the d pawn rather than face the assault! Jan understands this and would justify Nxe6 like.. "Hey it wins a pawn and white is in no danger! And if black tries to capture my E pawn, i move my rook to e1 and then I'll have some fun! So how could it be bad?" And it isn't. It's probably still sufficient for a win, its just that 13.a3 was stronger.
40/61 6:44:04 3,480,134k 144k +5.24 13.a3 Qc7 14.Rc1 h6 15.Be3 a6 16.Bxc6+ bxc6 17.b4 Ne4 18.Nxe4 dxe4 19.Rxc6 Qb7 20.Rxe6+ fxe6 21.Nxe6 Qd7 22.Qb3 Qc6 23.Bc5 Bxc5 24.bxc5 Ke7 25.Nxg7 Rh7 26.Nf5+ Kf8 27.Nd6 Qxc5 28.Qe6 Rb8 29.Qf5+ Kg7 30.Nxe4 Qe7 31.Nf6 Kh8 32.Nxh7 Qxh7 33.Qe6 Qg7 34.Rd1 a5 35.g3 Qf8 36.Qd6 Qxd6 37.exd6 Kg7 38.d7 Rd8 39.Rd6 a4 40.Kg2
40/61 42:49 842,925k 328k -1.59 13. ... Nxe6 14.Qxd5 Bb4 15.Be3 a6 16.Bxc6+ Rxc6 17.Rad1 0-0 18.Ne4 Qxd5 19.Rxd5 Re8 20.Rd7 Re7 21.Rfd1 Nf8 22.Rxe7 Bxe7 23.f4 Rc2 24.Rd2 Rxd2 25.Bxd2 f5 26.exf6 Bxf6 27.Nxf6+ gxf6 28.Kf2 f5 29.Kf3 h5 30.h3 Kf7 31.g4 hxg4+ 32.hxg4 fxg4+ 33.Kxg4 Ng6 34.Kf5 Nh4+ 35.Ke4 Ke6 36.b3 Nf5
46/69 2:38:10 2,876,084k 303k -1.45 13. ... Nxe6 14.Qxd5 Bb4 15.Be3 Bxc3 16.bxc3 Qxc3 17.Rac1 Qa3 18.Bxc6+ bxc6 19.Rxc6 0-0 20.Rfc1 Rxc6 21.Rxc6 h5 22.h3 Rb8 23.Rd6 a6 24.Rd7 Qb2 25.Kh2 Qb5 26.g3 Rf8 27.Rd6 Qa4 28.h4 Rb8 29.Rd7 Qb5 30.Kg2 Rf8 31.Qxb5 axb5 32.Ra7 Rd8 33.Kf3 g6 34.Ke4 b4 35.Rb7 Ra8 36.Rxb4 Rxa2 37.Rb7 Kg7 38.Kd5 Ra5+ 39.Kd6