Amazing game in latest TCEC match

[Andre]

Only computers can produce such games

[pgn]
[Event "TCEC Season 11 - Superfinal"]
[Site "http://tcec.chessdom.com"]
[Date "2018.04.12"]
[Round "79"]
[White "Stockfish 260318"]
[Black "Houdini 6.03"]
[WhiteElo "3546"]
[BlackElo "3489"]
[ECO "B12"]
[Result "1-0"]
1. e4 c6 2. d4 d5 3. e5 Bf5 4. h4 h6 5. g4 Bd7 6. Nd2 c5
7. dxc5 Nc6 8. Nb3 Nxe5 9. Qxd5 Nc6 10. Qg2 a5 11. Be3 a4
12. Nd2 a3 13. Rb1 Nf6 14. g5 Ng4 15. b4 hxg5 16. Bxg5 Bf5
17. Ngf3 g6 18. b5 Nd4 19. Nxd4 Qxd4 20. c6 f6 21. cxb7 Rb8
22. Qc6+ Bd7 23. Qc7 Qxf2+ 24. Kd1 Ne3+ 25. Bxe3 Bg4+
26. Be2 Qxe2+ 27. Kc1 Qxe3 28. Qxb8+ Kf7 29. Qd8 Bh6
30. b8=Q Qe4 31. Rf1 Bf5 32. Qxe7+ Kxe7 33. Qc7+ Ke6
34. Qc6+ Qxc6 35. bxc6 Rd8 36. Re1+ Kd6 37. Rb3 Kxc6
38. Re2 Ra8 39. Kd1 Bf4 40. Ke1 Ra4 41. c4 Ra8 42. Nf3 Kc5
43. h5 Kxc4 44. hxg6 Bxg6 45. Re6 Re8 46. Rxe8 Bxe8
47. Nd2+ Kd5 48. Rxa3 Kd4 49. Ra8 Bb5 50. Rc8 Kd5 51. Rd8+
Ke6 52. Nb3 Bc7 53. Rd4 Bc6 54. Rc4 Kd6 55. Nd4 Bd7 56. Ke2
Ba5 57. Nb3 Bc7 58. a4 Bh3 59. Rc1 Bd7 60. a5 Bc8 61. Kd3
f5 62. Kc3 f4 63. Kb4 Ba6 64. Rc2 f3 1-0
[/pgn]

[Nay Lin Tun]

Amazing! because SF took advantage of Houdini mistake. 56....Ke6??. Which I believe is the turning point from possible draw to lose. Why? The therory is there is a draw in K+B vs K+R+P (provided that white player's pawn is rook pawn or bishop pawn and the black players' bishop can dominate 7th rank of that pawn.In this case black must save "dark bishop")
Then black can tie other passed pawn with light color bishop and let white player exchange B+p vs N)

So black king must go 56....Kc6 and block white "a" pawn.

[Nay Lin Tun]

***51... Kc6, instead of Ke6.

[Paloma]

Houdini plays 56...Ba5, not ...Ke6

You mean probably 51...Ke6 is the mistake.

[Nay Lin Tun]

It is still hard, but theoretically, there is possible draw with K+R+P vs K+B
such as
[d]k7/8/P7/K1b5/8/8/8/4R3 w - - 3 1

(the same rule apply on "c" pawn as well)

So in theory, if black save dark bishop and make fortress like that, it is draw. (so let white take down light color bishop B+P vs N exchange)

Yes, I think, in position 51. ... black should better move his king to "a" file. 51...Kc6!!

[Nay Lin Tun]

This is the turning point in which black must decide which side his king will go.
[d]3R4/8/5p2/1b1k4/5b2/8/P2N4/4K3 b - - 6 51

[Nay Lin Tun]

Another known draw position, (not related to that game) K+R+P vs K+B
[d]2k5/8/2P5/3K4/8/8/7b/5R2 w - - 0 1