Structure de pions
♔ Blancs ♚ Noirs
Pions doublés
Pions isolés
Arriérés
Chaînes ● f7→g6, h7→g6
Passés
Majorité
Cases
♔ Blancs ♚ Noirs
Cases fortes ● d5 (2v0) ● b4 (2v0), ● d4 (2v1)
Cases faibles
Centre ● d5 (2v0), ● e4 (1v0) ● d4 (2v1), ● e5 (1v0)
Colonnes et diagonales
♔ Blancs ♚ Noirs
Pièces
♔ Blancs ♚ Noirs
Bc1 ● Bc1 Non développé (mob. 0)
Bf1 ● Bf1 Non développé (mob. 0)
Bc8 ● Bc8 Non développé (mob. 0)
Bf8 ● Bf8 Non développé (mob. 2)
Paire de fous ● Oui ● Oui
Non développées 4 (● c1, ● f1, ● a1, ● h1) 5 (● g8, ● c8, ● f8, ● a8, ● h8)
Sécurité du roi
♔ Blancs ♚ Noirs
Statut ● Au centre ● Au centre
Droits de roque O-O / O-O-O O-O / O-O-O
Thèmes
♔ Blancs ♚ Noirs
Phase Ouverture
Centre mobile
Ruptures ● d2-d4 ● …d7-d5, ● …f7-f5

B23n — Sicilian: Chameleon, 3…e5

1.e4 c5 2.Nc3 Nc6 3.Nge2 e5 *   ○ Trait aux Blancs

Ouverture — Centre mobile

♔ Point de vue Blancs

8 7 6 5 4 3 2 1
bR
bB
bQ
bK
bB
bN
bR
bP
bP
bP
bP
bP
bP
bN
bP
bP
Case forte (2v0)
wPPion central
wN
wP
wP
wP
wP
wN
wP
wP
wP
wR
wB
wQ
wK
wB
wR
abcdefgh
Plans. d4 (Occuper le centre — 77 % des parties) ; g3 (Préparer le fianchetto — 22 % des parties).

♚ Point de vue Noirs

1 2 3 4 5 6 7 8
wR
wB
wK
wQ
wB
wR
wP
wP
wP
wN
wP
wP
wP
wP
wN
wP
Case forte (2v1)
Case forte (2v0)
bP
bP
bN
bP
bP
bP
bP
bP
bP
bR
bN
bB
bK
bQ
bB
bR
hgfedcba
Plans. ...Bg7 (Fianchetto, fou sur la grande diagonale — 22 % des parties).
Avantages
Faiblesses
Diagonale active
Plans
Partie
1958 Hamburg Ch – Round 3 – Tscheppe, Karl-Heinz – 0-1 – Clemens, Christian, Dr. – G6
1. e4 c5 2. Ne2 Nc6 3. Nbc3 g6 4. d3 Bg7 5. Be3 Nd4 6. Qd2 e6 7. Nd1 b6 8. c3 Nc6 9. f4 Nge7 10. g4 Bb7
1964 UKR Ch – Round 2 – Kostiuchenko, Alexander – 1-0 – Shidkov – G10
1. e4 c5 2. Ne2 Nc6 3. Nbc3 g6 4. d3 d6 5. Be3 Bg7 6. Qd2 Nd4 7. Nd1 e5 8. c3 Ne6 9. d4 exd4 10. cxd4 Nf6
World Blitz 2019 – Round 13.41 – Vastrukhin, Oleg – 0-1 – Paravyan, David – G886
1. e4 c5 2. Nc3 Nc6 3. Nge2 g6 4. d3 Bg7 5. Be3 Nd4 6. Qd2 d6 7. Nd1 b5 8. c3 Nc6 9. d4 Nf6 10. f3 Nd7

B23n — Chameleon (1958)
1.e4 c5 2.Nc3 Nc6 3.Nge2 g6
Les coups candidats
4.d4 — 72.4% (2461 parties)
Ambassadeurs : Popov, Vladimir Valentinovich (17x), Huber, Gregory (16x), Soltis, Andrew (15x), De Heer, Machiel (12x), Kadric, Denis (12x), Knoppert, Erik (10x), Velickovic, Sasa (10x), Reinderman, Dimitri (9x)
4.g3 — 24.5% (833 parties)
Ambassadeurs : Westerinen, Heikki M.J. (12x), Mustonen, Ilkka (9x), Huber, Gregory (6x), Galdunts, Sergey (6x), Mariano, Jose Carlos N (6x), Boros, Daniel (6x), Leonard, Mark (5x), Zhong, Kevin (5x)
4.d3 — 1.9% (65 parties)
Ambassadeurs : Westerinen, Heikki M.J. (3x), Tscheppe, Karl-Heinz (2x), Montoya Bello, Felix J (2x), Vastrukhin, Oleg (2x), Alexander, Ken R D (1x), Shidkov, VS. (1x), Clemens, Christian, Dr. (1x), Koesler, Hans Dieter (1x)
4.h4 — 0.4% (13 parties)
Ambassadeurs : Berchtenbreiter, Maximilian (3x), Bagonyai, Attila (1x), Cao, Sang (1x), Arango, Andres Felipe (1x), Brito, Laila Pereira (1x), Silvio, Famorosa F (1x), Ameir, Moheb (1x), Chernyak, Viktoria (1x)
Analyse statistique des coups candidats
Répartition par niveau Elo (% des parties)
Tranche Elo N parties 4.d4 4.g3 4.d3 4.h4
<1800 160 53% 42% 5%
1800-2200 1332 65% 32% 2% 0%
2200-2600 1532 81% 17% 1% 0%
2600+ 31 94% 6%
Évolution par décennie (% des parties)
Décennie N parties 4.d4 4.g3 4.d3 4.h4
1950s 25 88% 4% 8%
1960s 66 89% 9% 2%
1970s 59 86% 14%
1980s 113 83% 16% 1%
1990s 811 73% 25% 1% 0%
2000s 767 70% 27% 2%
2010s 1039 70% 25% 2% 1%
2020s 517 73% 25% 2% 1%
Tendances récentes (2010s → 2020s)
Coup 2010s 2020s Δ
4.d4 70% 73% ▲ +2.1%
4.g3 25% 25% ▼ -0.7%
4.d3 2% 2% ▼ -0.6%
4.h4 1% 1% +0.0%
Joueurs célèbres
Champions du monde dans cette position
Hou, Yifan — 2 parties
Kasparov, Garry — 1 partie
Anand, Viswanathan — 1 partie
Parties historiques
4.d4 — 72.4% (2461 parties)
1950 — Keres, Paul Petrovich vs Averbakh, Yuri L — 1/2-1/2 — Szcawno Zdroj
1951 — Pachman, Ludek vs Barda, Olaf — 1-0 — Marianske Lazne zt
1952 — Fichtl, Jiri vs Sajtar, Jaroslav — 1-0 — Tatranska ch CZE
1953 — Matanovic, Aleksandar vs Dimc, Dragutin — 1-0 — Zagreb CRO
1953 — Barda, Yngvar vs Petri, Bernd — 0-1 — Copenhagen DEN
4.g3 — 24.5% (833 parties)
1956 — Franz, Joachim vs Zirngibl, Albert — 0-1 — GDR-ch Leipzig GER
1965 — Matas, Stanislav vs Rosenzweig, Vladimir — 1/2-1/2 — Vrbno pod Pradedem
1965 — Thiermann, Otto vs Pesch, Hans — 1/2-1/2 — Bamberg
1967 — Cormier, Kristian vs Mazzoni, Guy — 1/2-1/2 — Dieppe FRA
1969 — Fiala, Jiri vs Spacek, Petr — 1/2-1/2 — Cihak
4.d3 — 1.9% (65 parties)
1958 — Tscheppe, Karl-Heinz vs Clemens, Christian, Dr. — 0-1 — Hamburg GER
1958 — Tscheppe, Karl-Heinz vs Koesler, Hans Dieter — 1-0 — Hamburg GER
1964 — Alexander, Ken R D vs Shidkov, VS. — 1-0 — Kiev UKR
1985 — Stefanski, Mark E vs Groeller, W. — 0-1 — E Detroit Motor City op
1993 — Conquest, Stuart C vs Holland, Christopher — 1-0 — Hastings ENG
4.h4 — 0.4% (13 parties)
1996 — Bagonyai, Attila vs Cao, Sang — 1-0 — HUN-chT1 9596
2014 — Arango, Andres Felipe vs Brito, Laila Pereira — 1/2-1/2 — Praia da Pipa BRA
2014 — Silvio, Famorosa F vs Ameir, Moheb — 0-1 — Tiaret
2015 — Jobava, Baadur vs Shtembuliak, Evgeny — 1-0 — Minsk BLR
2017 — Berchtenbreiter, Maximilian vs Chernyak, Viktoria — 0-1 — Katowice POL