A10 English Opening: Unusual Replies for Black (1.c4 f5 2.Nc3 Nf6 3.d3 c6 4.g3 e6 5.Bg2 d5 6.cxd5 exd5 7.Nf3 Bd6 8.O-O O-O)

My opponent's reply to 1.c4, 1...f5 (16401 games, score 54.2%), is the 7th most often played move in the position, according to my reference database. More common moves against 1.c4 were 1...Nf6 (142556 games, score 54.5%), 1...e5 (106650 games, score 54.1%), 1...c5 (54778 games, score 55.1%), 1...e6 (53919 games, score 54.5%), 1...g6 (32975 games, score 52.5%) and 1...c6 (30736 games, score 55.1%). The second move by me, 2.Nc3 (5760 games, score 51.2%) is the most played move, but it does not score as well as 2.g3 (4303 games, score 55.6%) and 2.Nf3 (2850 games, score 55.7%), for instance. The reply 2...Nf6 (5366 games, score 51.1%) was the most popular choice among players. I then played 3.d3 (259 games, score 52.5%), which is the 4th most often played move, only behind the moves 3.g3 (3254 games, score 52.5%), 3.d4 (913 games, score 50.1%) and 3.Nf3 (773 games, 46.7%). The reply was the rarely seen move 3...c6, only two games in the database with a 50% score. The moves 3...g6 (99 games, score 51.5%), 3...e5 (75 games, score 52%), 3...e6 (56 games, score 54.5%), 3...d6 (33 games, 53%) and 3...b6 (5 games, score 40%) have been preferred more than what my opponent played in the game. Players rated 2055 and 2061 had played the move 3...c6. Due to the rare move order, this game went to previously unseen path when I played 4.g3. The only two moves seen in that position are 4.Bg5 and 4.e3 and both moves have been played once, according to my reference database. In the game where 4.Bg5 was played, White won and in the game where 4.e3 was played, Black won the game. However, in the latter game, the player who controlled the black pieces was over 500 points higher rated than the player who controlled the white pieces.

With my 5th move, Bg2 (4 games, score 50%) the game was brought back to previously played lines. 5.Bg2 is the most played move in the position. The next move 5...d5 (26 games, score 71.2%), gave even more reference games and it was also the most often played move. The game continued with the most popular moves in the position when I replied with the move 6.cxd5 (21 games, score 61.9%). The same pattern continued with the response 6...exd5 (18 games, score 63.9%). My 7th move, Nf3 (19 games, score 68.4%), has seen play by some strong players, the highest rated of them being Normunds Miezis, who was rated 2509 at the time of the game where the move 7.Nf3 was played by the Grand Master. The next move, 7...Bd6 (27 games, score 55.6%), was also most often played move. We kept following the game Normunds Miezis (2509) - Sascha Aulich (1908), played on October 4th, 2007, up to the move 8...O-O. Both moves 8.O-O (25 games, score 58%) and 8...O-O (80 games, score 63.3%) were most often played moves in the position. Once again there is a bit of a conflict in the notation of the novelty with my reference database, since the move 9.Bg5 has been played in 11 games with a score of 59.1%. It was the 2nd most played move, only behind the move 9.e4 (77 games, score 84.4%). Then Kojjootti played 9...Qe8 (2 games, score 100%), which was the 3rd most often played move. More often the moves 9...h6 (9 games, 38.9%) and 9...Nbd7 (3 games, score 66.7%) can be seen in the database. The next move 10.Qb3 had been seen only once before and in that game the player controlling the white pieces won the game. The move 10...Kh8 is actually the real novelty that was played in this game. Previously the move 10...Nbd7 was played in that position.

[Event "Live Chess"] [Site "Chess.com"] [Date "2016.07.18"] [Round "?"] [White "Vierjoki, Timo"] [Black "Kojjootti"] [Result "0-1"] [ECO "A10"] [WhiteElo "1774"] [BlackElo "1724"] [Annotator "Stockfish 9 64 POPCNT (30s)"] [PlyCount "84"] [EventDate "2016.??.??"] 1. c4 f5 2. Nc3 Nf6 3. d3 c6 4. g3 e6 5. Bg2 d5 6. cxd5 exd5 7. Nf3 Bd6 8. O-O O-O {A10 English Opening: Unusual Replies for Black} 9. Bg5 $146 (9. e3 Nbd7 10. a3 Qe8 11. b4 a6 12. Re1 Qg6 13. Nh4 Qf7 14. Nxf5 Bc7 15. f4 Bb6 16. Bb2 Re8 17. Kf2 Nf8 18. Nd6 Ng4+ 19. Qxg4 Bxg4 {1/2-1/2 (19) Burzler,A-Antusch,I Germany 1997}) (9. e4 dxe4 10. dxe4 Nxe4 11. Nxe4 fxe4 12. Qb3+ Kh8 $16) 9... Qe8 $2 (9... h6 10. Bd2 $14) 10. Qb3 (10. Bxf6 Rxf6 11. e4 dxe4 12. dxe4 Bc5 $18) 10... Kh8 (10... Nbd7 11. Qc2 $14) 11. Rfe1 (11. e3 Nbd7 $14) 11... Nbd7 ( 11... Na6 $14) 12. d4 (12. e3 $142 $5 $16) 12... Ne4 13. Nxe4 $2 (13. Bf4 $5 { is worthy of consideration} Bxf4 14. gxf4 $15) 13... fxe4 $17 14. Nd2 Qh5 15. Be3 Nf6 16. f3 exf3 (16... a5 17. a4 $17) 17. exf3 b6 (17... a5 18. Re2 $15) 18. Rac1 {White threatens to win material: Rc1xc6} (18. Qc2 Bd7 $11) 18... Bd7 19. Bf2 (19. Nf1 Rae8 $15) 19... g5 (19... h6 20. a3 $11) 20. Re3 (20. Nf1 Qg6 $15) 20... g4 (20... Qf7 21. Rce1 $15) 21. f4 {White has a new protected passed pawn: f4} c5 $4 {Black lets it slip away} (21... Qg6 22. Nf1 $15) 22. Re2 $4 {overlooking an easy win} (22. dxc5 $142 {and White could have gained the advantage} bxc5 23. Qa3 $18) 22... c4 $11 {Black gets more space} 23. Qc2 ( 23. Qd1 Qf7 $11) 23... Bf5 (23... Bxf4 24. Qc3 Bf5 $17) 24. Qa4 $2 (24. Qd1 Qg6 $15) 24... Bd7 $4 {Black threatens to win material: Bd7xa4. a transit from better to worse} (24... Bxf4 $142 {and the scales tip in favour of Black} 25. Rce1 Bd3 $17) 25. Qd1 $11 b5 (25... Qf7 $11) 26. Qe1 (26. Re5 Qf7 $11 (26... Bxe5 $2 27. dxe5 (27. fxe5 $143 Ng8 $17) 27... Ng8 28. Ne4 $18)) 26... Rae8 ( 26... Bf5 $15) 27. Rxe8 (27. Re5 $142 $5 {is a viable option} Bf5 28. Nf1 $11) 27... Rxe8 $17 (27... Bxe8 $6 28. Nf1 $11) (27... Qxe8 $6 28. Nf1 $15) ({ Instead of} 27... Nxe8 28. Nf1 $14) 28. Qf1 (28. Qd1 $5 $17) 28... Qg6 $19 29. Re1 $4 {the position was bad, and this mistake simply hastens the end} (29. Qd1 $142 Bf5 30. Nf1 $19) 29... Rxe1 (29... Qc2 $142 {keeps an even firmer grip} 30. Rxe8+ Bxe8 31. Qe1 $19) 30. Qxe1 Bf5 (30... Qc2 $142 {and Black has triumphed} 31. Nf1 Qxb2 $19) 31. Nf1 $11 {White has a cramped position} Ne4 ( 31... b4 32. Ne3 Be4 33. f5 Bxf5 34. Nxd5 Nxd5 35. Bxd5 $11) 32. Ne3 (32. Qa5 Bf8 (32... Nxf2 $143 33. Kxf2 Be4 34. Qd8+ Kg7 35. Qd7+ Kg8 36. Bxe4 Qxe4 37. Qxg4+ (37. Qxd6 $6 Qxd4+ 38. Ke1 Qe4+ 39. Kd1 Qf3+ 40. Ke1 Qe4+ 41. Kd1 Qf3+ 42. Ke1 Qe4+ $11) 37... Kf8 38. Ne3 $16) 33. Qd8 Qd6 34. Qxd6 Nxd6 $14) 32... Nxf2 (32... Be6 33. a4 Bf8 34. axb5 Nxf2 35. Kxf2 $11) 33. Qxf2 {Black has the pair of bishops} (33. Kxf2 Qf6 34. Qc3 Bf8 $14) 33... Qe6 (33... Be4 $5 34. f5 Qg5 $11) 34. Bxd5 $14 Qd7 (34... Qf6 35. Bc6 $14) 35. Nxf5 (35. h3 $142 $5 $16) 35... Qxf5 $14 36. Bc6 Qb1+ 37. Kg2 b4 $2 (37... Qd3 $142 $14) 38. d5 $4 { throws away the game} (38. Qe2 $142 $18 {with excellent chances for White}) 38... Qd1 $4 {makes life more difficult} (38... Qe4+ $142 {seems even better} 39. Kf1 c3 $19) 39. Bb5 $4 {throws away a nice position} (39. Qe3 $142 $11 { would be a reprieve}) 39... c3 (39... Qxd5+ 40. Kf1 Bc5 41. Qc2 b3 42. Qc3+ Bd4 43. Bc6 Qc5 44. Qxd4+ Qxd4 45. axb3 cxb3 46. Ke1 Qxb2 47. Be4 Qd4 48. Bf5 Qc5 49. Bb1 Qc1+ 50. Kf2 Qxb1 51. Ke3 b2 52. h3 Qc1+ 53. Kd4 b1=Q 54. hxg4 Qb6+ 55. Ke5 Qce3+ 56. Kf5 Qg6#) 40. bxc3 (40. Ba4 Qxa4 41. Qd4+ Kg8 42. Qe4 $19) 40... bxc3 41. Qe2 (41. Ba4 {hardly improves anything} Qxd5+ 42. Kf1 Qc4+ 43. Ke1 Qxa4 44. Qe3 Qc6 45. Qe6 c2 46. Qf6+ Kg8 47. Qg5+ Kf7 48. Qf5+ Ke7 49. Qxh7+ Kd8 50. Qg8+ Kc7 51. Qg7+ Kc8 52. Qh8+ Kd7 53. Qh7+ Be7 54. Qf5+ Kd8 55. Qd3+ Kc8 56. Qf5+ Kb7 57. Qxc2 Bb4+ 58. Kf2 Qxc2+ 59. Kf1 Qd1+ 60. Kg2 Qf3+ 61. Kg1 Bc5#) 41... Qxe2+ (41... Qxd5+ 42. Kf2 Bc5+ 43. Ke1 Qh1+ 44. Qf1 Qe4+ 45. Qe2 Qb1+ 46. Qd1 c2 47. Qxb1 cxb1=Q+ 48. Kd2 Qb2+ 49. Kd3 Qd4+ 50. Ke2 Qe3+ 51. Kd1 Bb4 52. Kc2 Qc3+ 53. Kb1 Ba3 54. h3 Qb2#) 42. Bxe2 c2 (42... c2 43. Bxg4 c1=Q 44. Bf3 Qb2+ 45. Kh3 Qf2 46. Bh5 Qf1+ 47. Kg4 Qd1+ 48. Kg5 Be7+ 49. Kf5 Qxh5+ 50. Ke4 Bc5 51. d6 Qg6+ 52. f5 Qg4+ 53. Kd5 Qd4+ 54. Kc6 Qxd6+ 55. Kb5 a6+ 56. Kc4 Qd4+ 57. Kb3 Qd3+ 58. Kb2 Ba3+ 59. Ka1 Qd1#) 0-1

Another set of the latest and highest rated reference games can be seen below.

[Event "MGL-ch 55th"] [Site "Ulaanbaatar"] [Date "2015.04.21"] [Round "6"] [White "Mungunkhuu, Mijgee"] [Black "Munkhgal, Gombosuren"] [Result "0-1"] [ECO "A10"] [WhiteElo "2202"] [BlackElo "2419"] [PlyCount "112"] [EventDate "2015.04.18"] [EventType "tourn"] [EventRounds "13"] [EventCountry "MGL"] [EventCategory "3"] [SourceTitle "Mega2015 Update 24"] [Source "Chessbase"] [SourceDate "2015.05.08"] 1. c4 f5 2. Nc3 Nf6 3. d3 e6 4. Nf3 d5 5. cxd5 exd5 6. g3 c6 7. Bg2 Bd6 8. O-O O-O 9. a3 a5 10. Bg5 h6 11. Bd2 Nbd7 12. Qc2 Nc5 13. b4 Ne6 14. Rab1 f4 15. b5 fxg3 16. hxg3 Bxa3 17. bxc6 bxc6 18. Qa4 Bc5 19. Ne5 Qd6 20. Qxc6 Qxe5 21. Qxa8 Ng4 22. Qxd5 Qxg3 23. Qh5 Nxf2 24. Nd5 Nd1+ 25. Be3 Nxe3 26. Rxf8+ Nxf8 27. Nxe3 Bxe3+ 28. Kh1 Bg4 29. Bd5+ Kh8 30. Qh2 Qxh2+ 31. Kxh2 Bxe2 32. Kg2 Bc5 33. Rb5 Bb4 34. Be4 Bg4 35. d4 Kg8 36. Rb7 Bd7 37. Bd5+ Be6 38. Be4 Bd7 39. Bd5+ Kh8 40. Kf3 Be7 41. Ra7 a4 42. Bf7 a3 43. Ke4 g5 44. Ke5 Kg7 45. Be8 Bxe8 46. Rxe7+ Bf7 47. Ra7 Ng6+ 48. Kf5 a2 49. d5 Ne7+ 50. Ke5 Nxd5 51. Rxa2 Nf4 52. Ra6 Be6 53. Ra7+ Kg6 54. Ra6 h5 55. Ke4 h4 56. Kf3 Kf5 0-1 [Event "Andorra op 33rd"] [Site "Erts"] [Date "2015.07.25"] [Round "8"] [White "Berkovich, Mark A"] [Black "Simon Padros, Emili"] [Result "1/2-1/2"] [ECO "A04"] [WhiteElo "2376"] [BlackElo "2229"] [PlyCount "100"] [EventDate "2015.07.18"] [EventType "swiss"] [EventRounds "9"] [EventCountry "AND"] [SourceTitle "Mega2015 Update 36"] [Source "Chessbase"] [SourceDate "2015.07.31"] 1. Nf3 e6 2. g3 f5 3. Bg2 Nf6 4. O-O d5 5. c4 c6 6. Nc3 Bd6 7. d3 O-O 8. cxd5 exd5 9. e4 Bb4 10. exd5 Bxc3 11. bxc3 Nxd5 12. c4 Nf6 13. Rb1 Na6 14. Be3 h6 15. Qb3 Re8 16. d4 Re7 17. Ne5 Be6 18. Rfd1 Kh7 19. Qa4 Qc8 20. d5 cxd5 21. cxd5 Bd7 22. Qd4 Ne4 23. Nxd7 Qxd7 24. Rbc1 b6 25. Qd3 Nac5 26. Qc2 Rc8 27. Bf4 g6 28. h4 Ree8 29. Qb2 Qg7 30. Qxg7+ Kxg7 31. d6 Rcd8 32. Rd5 g5 33. hxg5 hxg5 34. Bxe4 Nxe4 35. Be5+ Kf7 36. f3 Nc5 37. Bd4 Ke6 38. Re5+ Kxd6 39. Rxf5 Ne6 40. Be3 Rc8 41. Rd1+ Ke7 42. Re1 Kd6 43. Rf6 Kd5 44. Rd1+ Ke5 45. Rf7 Rf8 46. Rdd7 Rxf7 47. Rxf7 Rc3 48. f4+ gxf4 49. Bxf4+ Nxf4 50. gxf4+ Ke4 1/2-1/2 [Event "Manacor 7th"] [Site "Manacor"] [Date "2016.02.25"] [Round "6"] [White "Salomon, Johan"] [Black "Stremavicius, Titas"] [Result "0-1"] [ECO "A04"] [WhiteElo "2450"] [BlackElo "2468"] [PlyCount "138"] [EventDate "2016.02.21"] [EventType "tourn"] [EventRounds "9"] [EventCountry "ESP"] [EventCategory "10"] [SourceTitle "Mega2016 Update 22"] [Source "Chessbase"] [SourceDate "2016.03.03"] 1. Nf3 f5 2. d3 d5 3. c4 e6 4. cxd5 exd5 5. g3 Nf6 6. Bg2 Bd6 7. O-O O-O 8. Nc3 c6 9. e4 fxe4 10. dxe4 Nxe4 11. Nxe4 dxe4 12. Ng5 Be7 13. Qh5 Bxg5 14. Bxg5 Qe8 15. Qxe8 Rxe8 16. Rae1 Bf5 17. f3 Nd7 18. fxe4 Be6 19. Rd1 Ne5 20. a3 h6 21. Bf4 Nc4 22. Bc1 Rad8 23. h3 a5 24. g4 a4 25. Kf2 Ne5 26. Kg3 Bb3 27. Rxd8 Rxd8 28. Kf4 Nc4 29. Kg3 Rd3+ 30. Kh2 Rd7 31. Rf5 g6 32. Rf2 Kg7 33. Bf1 Nd6 34. Bg2 Re7 35. Rd2 Nc4 36. Rd8 g5 37. Bd2 Nxd2 38. Rxd2 Kf6 39. Rd6+ Re6 40. Rd7 b5 41. Kg3 Ke5 42. Kf2 Rd6 43. Rxd6 Kxd6 44. e5+ Kd7 45. Be4 c5 46. Bf5+ Ke7 47. Ke3 b4 48. Kd2 Bd5 49. Kd3 Bb3 50. Kd2 Bc4 51. Bc2 Bb5 52. Bf5 Bf1 53. Bc2 Bxh3 54. Bxa4 Bxg4 55. Bb3 Be6 56. Bd1 bxa3 57. bxa3 Bd5 58. Bg4 h5 59. Bxh5 Ke6 60. a4 Kxe5 61. Ke3 Kf5 62. Be2 g4 63. a5 g3 64. a6 g2 65. Kf2 Ke5 66. Bg4 c4 67. Bd1 c3 68. a7 Kd4 69. Bc2 Kc5 0-1 [Event "Ulaanbaatar Ikh Nuudel op"] [Site "Ulaanbaatar"] [Date "2016.10.01"] [Round "3"] [White "Mungunkhuu, Mijgee"] [Black "Bilguun, Sumiya"] [Result "0-1"] [ECO "A10"] [WhiteElo "2240"] [BlackElo "2444"] [PlyCount "52"] [EventDate "2016.09.29"] [EventType "swiss"] [EventRounds "9"] [EventCountry "MGL"] [SourceTitle "Mega2016 Update 53"] [Source "Chessbase"] [SourceDate "2016.10.08"] 1. c4 f5 2. Nc3 Nf6 3. d3 e6 4. Nf3 d5 5. cxd5 exd5 6. g3 c6 7. Bg2 Bd6 8. O-O O-O 9. Rb1 a5 10. a3 Na6 11. Bg5 h6 12. Bxf6 Qxf6 13. Qc2 f4 14. Na4 Bg4 15. Qc3 Qe7 16. Rfe1 Nc7 17. Rbc1 Rae8 18. d4 Nb5 19. Qd2 Qf6 20. Rcd1 fxg3 21. hxg3 Re4 22. Rf1 Bxf3 23. exf3 Rxd4 24. Qc2 Rc4 25. Nc3 Nxc3 26. bxc3 Rxc3 0-1