Gentlemen, start your engines: A 2 ply novelty

[Dann Corbit]

http://www.chessdom.com/a-novelty-on-mo ... s-history/

Sound or not?

[elpapa]

[pgn][Event "2018 Spring Chess Classic A"]
[White "Shankland, Samuel"]
[Black "Ipatov, Alexander"]
[Site "Saint Louis"]
[Round "8"]
[Annotator "TA"]
[Result "1/2-1/2"]
[Date "2018.03.13"]
[WhiteElo "2668"]
[BlackElo "2665"]
[PlyCount "78"]

1. d4 {} Na6 (1... Nf6 2. c4 e6 3. Nc3 Bb4 4. Qc2 d5 5. cxd5 Qxd5 6. e3 c5 7. Bd2 Bxc3 8. Bxc3 cxd4 9. Bxd4 Nc6 10. Bc3 0-0 11. Nf3 Rd8 12. Be2 Qe4 13. Rc1 Qxc2 14. Rxc2 Nd5 15. Ne5 Bd7 16. Nxc6 Bxc6 17. Bd2 Ne7 18. f3 {1/2-1/2 (38) Mamedyarov,S (2804)
-Carlsen,M (2834) Wijk aan Zee 2018} )2. c4 e5 $146 ({Predecessor:} 2... c6 3. Nc3 d6 4. e4 e5 5. d5 Be7 6. f4 exf4 7. Bxf4 Nf6 8. Bd3 Nc5 9. Bc2 {1-0 (22)
Monell Camarasa,D (2340)-Monfa Sole,R (2160) Tornabous 2014} )3. dxe5 d6 4. Nf3 Bf5 5. Bg5 Qd7 6. Nc3 {aiming for e4. A40: Unusual replies to 1 d4} dxe5 $1 7. Qxd7+ ({But not} 7. Nxe5 Qxd1+ 8. Rxd1 f6 $15 )Bxd7 8. Nxe5 {White is
slightly better.} Be6 $1 9. Bf4 0-0-0 10. e3 (10. a3 {feels hotter.} f6 11. Nf3 Bxc4 12. e3 Bxf1 13. Kxf1 Ne7 14. Ke2 )Nf6 11. Be2 {next a3 is good for
White.} Bb4 $1 12. 0-0 (12. Rc1 $11 )Bxc3 $1 $15 13. bxc3 Ne4 $1 14. Rfc1 Rd2 { Black has compensation.} 15. Bf3 (15. Re1 $1 $11 {keeps the
balance.} )f5 16. Bg3 {} Rhd8 {} 17. Bh4 R8d6 18. Be7 Rb6 19. Rd1 Rbb2 20. Bxe4 fxe4 21. Rxd2 Rxd2 22. Kf1 Nb8 23. Ke1 Rc2 24. Rd1 { [#]} Nd7 25. Nxd7 Bxd7 $11 { Endgame KRB-KRB} 26. Rd4 Rxa2 27. Rxe4 Ra1+ 28. Kd2 Ra2+ 29. Ke1 a5 30. Rh4 a4 31. Rxh7 {Black must now
prevent Rh8+.} b6 32. Rh8+ Kb7 33. Rd8 Ra1+ 34. Ke2 $1 Be6 {[#] Threatens to
win with ...a3.} 35. Rd1 $1 { The position is equal.} Bxc4+ 36. Ke1 $1 $132 { White is not keeping still} Ra2 37. Rd2 $1 Ra1+ 38. Rd1 Ra2 39. Rd2 $1 Ra1+ {Precision: White = 69%, Black = 71%.} 1/2-1/2[/pgn]

[Dann Corbit]

[d]rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - acd 59; acs 2569364; bm e4; c0 "e4"; c2 "perft 1 20 perft 2 400 perft 3 8902 perft 4 197281 perft 5 4865609 perft 6 119060324"; c3 "d4"; c4 "c4"; cce 38; ce 13; id "Fundamental Opening Position"; pm e4 {2379495} d4 {1725526} Nf3 {483679} c4 {479713} g3 {39820} f4 {35589} b3 {27764} Nc3 {13010} e3 {2686} b4 {2458} g4 {2450} c3 {1654} d3 {1649} a3 {1150} h3 {717} a4 {552} h4 {425} f3 {363} Nh3 {82} Na3 {28}; pv e4 c5 Nf3 d6 Bb5+ Nd7 d4 cxd4 Nxd4 Nf6 Bd3 Nc5 Nc3 g6 f3 Bg7 Be3 O-O Be2 Qc7 O-O a6 Qd2 Rd8 Nd5 Nxd5 exd5 Bd7 c3 Re8 Rfe1 e6 dxe6 Nxe6 Nb3 Rad8 Bf1 Ba4 Qf2 Qc6 Nd4 Nxd4 Bxd4 Bxd4 Qxd4 Qc5 Kf2 Qxd4+ cxd4 Rc8 Bd3 Bb5 Rxe8+ Rxe8 Be4 f5 Bd5+ Kg7 a4 Re2+ Kg3 Bd7 Bxb7 g5 Kh3 Rxb2 Bxa6 f4+ g4 Bc6; white_wins 1826279; black_wins 1425008; draws 1430947; Opening Fundamental opening position;

[d]rnbqkbnr/pppppppp/8/8/3P4/8/PPP1PPPP/RNBQKBNR b KQkq - acd 48; acs 226889; bm e6; c3 "Na6"; cce -42; ce -12; pm Nf6 {1004729} d5 {434599} e6 {116089} f5 {63006} d6 {40940} g6 {32622} c5 {15043} c6 {6638} Nc6 {3907} b6 {2255} e5 {1558} b5 {1162} a6 {822} h6 {540} Na6 {446} a5 {334} h5 {316} g5 {233} f6 {171} Nh6 {117}; pv e6 c4 Nf6 Nf3 b6 g3 Be7 Bg2 Bb7 O-O O-O Nc3 Ne4 Qd3 Nxc3 Qxc3 c5 Rd1 Na6 b3 Bf6 Bb2 Rc8 Rac1 d5 Qe3 Nb4 Ne5 cxd4 Bxd4 Nxa2 Ra1 Nb4 Rxa7 Nc2 Qd2 Nxd4 Qxd4 dxc4 Bxb7 Bxe5 Qxd8; white_wins 597411; black_wins 453117; draws 491802; Opening Queen Pawn Opening: General. 1.d4; CaxtonID: 1623; ECO: A40;

The correct move (according to chess engine analysis) was made here:
[d]r1bqkbnr/pppppppp/n7/8/3P4/8/PPP1PPPP/RNBQKBNR w KQkq - acd 37; acs 1659; bm c4; c3 "c4"; cce -10; ce 54; pm e4 {338} Nc3 {40} Nf3 {30} e3 {13} c4 {11} a3 {5} Bg5 {2} Nd2 {2} c3 {2} Be3 {1} Kd2 {1} d5 {1}; pv c4 f5 g3 Nf6 Nf3 g6 Bg2 Bg7 O-O O-O Nc3 d6 Bg5 c6 Qd2 Nc7 d5 Bd7 Bh6 cxd5 Bxg7 Kxg7 cxd5 a5 a3 Rc8 Rfc1 Na6 Nd4 Nc5 Rc2 Nce4 Nxe4 Rxc2 Nxc2 fxe4 Ne3 Qb6 Nc4; white_wins 175; black_wins 185; draws 75; Opening A40 Australian Defense;

Computer analysis says that f5 (never played in an actual game) is the best response. The move e5 lost half a pawn.
[d]r1bqkbnr/pppppppp/n7/8/2PP4/8/PP2PPPP/RNBQKBNR b KQkq - acd 36; acs 2398; bm f5; c3 "e5"; cce -205; ce -53; pm e6 {5} Nf6 {4} c5 {1} c6 {1} d6 {1} g6 {1}; pv f5 g3 Nf6 Nf3 g6 Bg2 Bg7 O-O O-O Nc3 d6 Bg5 c6 Qd2 Nc7 d5 Bd7 Bh6 cxd5 Bxg7 Kxg7 cxd5 a5 a3 Rc8 Rfc1 Na6 Nd4 Nc5 Rc2 Nce4 Nxe4 Rxc2 Nxc2 fxe4 Ne3 Qb6 Nc4; white_wins 8; black_wins 2; draws 3;