A restrictive pawn sacrifice

[Nordlandia]

« For the price of a pawn Black has effectively shut his opponent's bishop out of the game. Moroever, it is far from clear how and when White will be able to address this problem, especially if Black endeavours to keep White busy elsewhere. » - Understanding the Sacrifice: Sacrifice Your Way to Success (2002 Everyman Chess)

Latest stockfish assesses the position after white's ...Bh2 as almost equal, just tiny better for black. Lco evaluation suggest -1,3 edge for black.

[d]r4rk1/pp6/1bn1R2p/6pb/5p2/1NP2N1P/PP3PPB/3R2K1 b - - 0 6

[pgn][Event "Canada op"] [Site "Edmonton"] [Date "2000.07.08"] [EventDate "?"] [Round "10"] [Result "0-1"] [White "Peter K Wells"] [Black "Jonathan Rowson"] [ECO "A41"] [WhiteElo "2498"] [BlackElo "2591"] [PlyCount "72"] 1.d4 d6 2.Nf3 Bg4 3.e4 Nf6 4.Bd3 e6 5.h3 Bh5 6.O-O d5 7.Nbd2 Be7 8.c3 O-O 9.exd5 exd5 10.Re1 c5 11.dxc5 Bxc5 12.Nb3 Bb6 13.Bg5 h6 14.Bh4 Nc6 15.Bf5 g5 16.Bg3 Ne4 17.Bxe4 dxe4 18.Rxe4 f5 19.Re6 Qxd1+ 20.Rxd1 f4 21.Bh2 Rad8 22.Rxd8 Rxd8 23.Nfd2 Bf7 24.Re2 Bc4 25.Re1 Ne5 26.Nxc4 Nxc4 27.Kf1 Nxb2 28.g3 f3 29.g4 Bxf2 30.Kxf2 Nd3+ 31.Kf1 Nxe1 32.Kxe1 Re8+ 33.Kf1 Re2 34.Bg3 Rxa2 35.Nd4 a5 36.Nxf3 a4 0-1[/pgn]

[Eelco de Groot]

Took a look at it with old Kaissa II in Multi PV. In the game, exchange of Rooks on d8 seems not to hurt but after that, White move 23. Nfd2 is probably inaccurate. Kaissa probably can't see an inmobile B though. In the main line with Nbd2 plays g3 and gets B moving at the cost of a castle pawn against storm pawn.

[d]3r2k1/pp6/1bn1R2p/6pb/5p2/1NP2N1P/PP3PPB/6K1 w - -

Engine: Kaissa II (512 MB)
by T. Romstad, M. Costalba, J. Kiiski, G. Linscott

41 150:19 -0.27 23.Nbd2 Bf7 24.Re2 Bxa2 25.g3 fxg3
26.Bxg3 Kf8 27.Ne4 Rd1+ 28.Kg2 Kg7
29.Rd2 Rxd2 30.Nfxd2 Bd5 31.f3 Kg6
32.Nd6 Be3 33.N6c4 Bf4 34.Bxf4 gxf4
35.b4 Be6 36.b5 (19.604.446.931) 2173

41 150:19 -0.56 23.Nbd4 Bf7 24.Re2 Nxd4 25.Nxd4 Bxd4
26.cxd4 Rxd4 27.Kh1 Bxa2 28.f3 Rd7
29.Bg1 b6 30.Re4 Bd5 31.Rd4 Kf7
32.Rd2 Ke6 33.Bd4 Bc4 34.Bc3 Rxd2
35.Bxd2 Bd5 36.h4 (19.604.446.931) 2173

41 150:19 -0.84 23.Nfd4 Bf7 24.Re1 Nxd4 25.Nxd4 Bxd4
26.cxd4 Bxa2 27.Ra1 Be6 28.Rxa7 Rxd4
29.Kh1 Rd2 30.f3 Rxb2 31.Bg1 Bc4
32.Ra1 b5 33.Bd4 Rc2 34.Ra6 Bf1
35.Rxh6 Bxg2+ 36.Kg1 (19.604.446.931) 2173

41 150:19 -0.97 23.Nfd2 a5 24.a4 Bf7 25.Re1 Ne5
26.Bxf4 Nc4 27.Nxc4 Bxc4 28.Be3 Bxe3
29.Nxa5 Bd2 30.Nxb7 Rd7 31.Re8+ Kf7
32.Rd8 Rxd8 33.Nxd8+ Ke7 34.Nc6+ Kd6
35.Na5 Bd5 36.Kf1 (19.604.446.931) 2173