Structure de pions

	♔ Blancs	♚ Noirs
Pions doublés	—	—
Pions isolés	—	—
Arriérés	—	—
Chaînes	● b2→a3, f2→e3, e3→d4	● b7→a6, f7→e6
Passés	—	—
Majorité	—	● aile dame 3v2

Cases

	♔ Blancs	♚ Noirs
Cases fortes	● e5 (2v0)	● d5 (3v1)
Cases faibles	—	—
Centre	● d4 (3v2), ● e5 (2v0)	● d5 (3v1), ● e4 (1v0)

Colonnes et diagonales

	♔ Blancs	♚ Noirs
Semi-ouvertes	● c	● d

Pièces

	♔ Blancs	♚ Noirs
Bc1	● Bc1 Non développé (mob. 1)
Bc4	● Bc4 Actif (mob. 8)
Bc8		● Bc8 Non développé (mob. 1)
Bf8		● Bf8 Non développé (mob. 2)
Paire de fous	● Oui	● Oui
Non développées	3 (● b1, ● c1, ● a1)	5 (● b8, ● c8, ● f8, ● a8, ● h8)

Sécurité du roi

	♔ Blancs	♚ Noirs
Statut	● Roqué	● Au centre
Droits de roque	—	O-O / O-O-O

Thèmes

	♔ Blancs	♚ Noirs
Phase	Ouverture
Centre	mobile
Ruptures	● d4-d5	● …e6-e5

D27a — QGA: Classical, 6…a6 7.a3

1.d4 d5 2.c4 dxc4 3.Nf3 Nf6 4.e3 e6 5.Bxc4 c5 6.O-O a6 7.a3 * ● Trait aux Noirs

Ouverture — Centre mobile

♔ Point de vue Blancs

8 7 6 5 4 3 2 1

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Plans. Ba2 (55 % des parties) ; Be2 (18 % des parties) ; Bd3 (Fou actif (mobilité 9) — 9 % des parties).

♚ Point de vue Noirs

1 2 3 4 5 6 7 8

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Plans. ...b5 (Expansion aile dame — 83 % des parties) ; ...Nc6 (Développer b8 — 6 % des parties).

Avantages

Faiblesses

Diagonale active

Plans

Partie
1908 Prague – Round 9 – Duz-Khotimirsky, Fedor Ivanovich – 1/2-1/2 – Maroczy, Geza – G76 1. d4 d5 2. Nf3 c5 3. e3 e6 4. c4 Nf6 5. a3 dxc4 6. Bxc4 a6 7. O-O b5 8. Bd3 Nbd7 9. Qe2 Bb7 10. Rd1 Qb6
1935 Buenos Aires – Round 1 – Guimard, Carlos E – 1-0 – Hounie Fleurquin, Carlos – G4 1. d4 d5 2. c4 e6 3. Nf3 Nf6 4. e3 c5 5. a3 dxc4 6. Bxc4 a6 7. O-O b5 8. Bd3 cxd4 9. exd4 Bb7 10. Qe2 Be7
1937 Brno – Round 11 – May, Desider – 1/2-1/2 – Koblencs, Alexander – G22 1. d4 d5 2. Nf3 Nf6 3. c4 dxc4 4. e3 e6 5. Bxc4 c5 6. O-O a6 7. a3 Nc6 8. dxc5 Qxd1 9. Rxd1 Bxc5 10. b4 Be7
1937 Semmering/Baden – Round 1 – Reshevsky, Samuel – 1-0 – Petrov, Vladimir (ENG) – G4 1. Nf3 Nf6 2. d4 d5 3. c4 dxc4 4. e3 e6 5. Bxc4 c5 6. O-O a6 7. a3 b5 8. Ba2 Bb7 9. Qe2 Nbd7 10. Rd1 cxd4
1947 Leningrad ch-URS – Round 3 – Ragozin, Viacheslav – 1-0 – Klaman, Konstantin Mikhailovich – G52 1. d4 d5 2. c4 dxc4 3. Nf3 c5 4. e3 Nf6 5. Bxc4 e6 6. O-O a6 7. a3 Nbd7 8. Nc3 Be7 9. Qe2 b5 10. Ba2 Bb7
1960 Mar del Plata – Round 5 – Letelier Martner, Rene – 1/2-1/2 – Aguilera Bazan, Oscar – G49 1. d4 d5 2. c4 dxc4 3. e3 Nf6 4. Bxc4 a6 5. a3 e6 6. Nf3 c5 7. O-O b5 8. Ba2 Bb7 9. Nc3 Nbd7 10. Qe2 Qc7
36. Olympiad 2004 – Round 7 – Kozul, Zdenko – 1/2-1/2 – Charbonneau, Pascal – G225 1. d4 d5 2. c4 dxc4 3. Nf3 Nf6 4. e3 e6 5. Bxc4 c5 6. O-O a6 7. a3 b5 8. Ba2 Bb7 9. Nc3 Nbd7 10. Re1 Be7
Clarin 1979 – Round 2 – Andersson, Ulf 1949 – 1/2-1/2 – Petrosian, Tigran V – G7 1. Nf3 Nf6 2. d4 d5 3. c4 dxc4 4. e3 e6 5. Bxc4 c5 6. O-O a6 7. a3 cxd4 8. Nxd4 Bd6 9. Nf3 O-O 10. Qe2 Nc6
World Blitz 2019 – Round 21.10 – Saini Vidit – 0-1 – Inarkiev, Ernesto – G1394 1. d4 d5 2. c4 dxc4 3. e3 Nf6 4. Bxc4 e6 5. Nf3 c5 6. O-O a6 7. a3 Nc6 8. dxc5 Bxc5 9. b4 Bd6 10. Bb2 O-O
World Blitz 2021 – Round 4.6 – Saini Vidit – 1-0 – Vachier-Lagrave, Maxime – G243 1. Nf3 d5 2. d4 Nf6 3. c4 dxc4 4. e3 e6 5. Bxc4 c5 6. O-O a6 7. a3 Nbd7 8. dxc5 Bxc5 9. b4 Be7 10. Bb2 b5

D27a — QGA: Classical (1908)

1.d4 d5 2.c4 dxc4 3.Nf3 Nf6 4.e3 e6 5.Bxc4 c5 6.O-O a6 7.a3

Les coups candidats

7…b5 — 83.3% (305 parties)

Ambassadeurs : Kozul, Zdenko (16x), Atalik, Suat (6x), Piskov, Yury (4x), Ivanisevic, Ivan (4x), Gyimesi, Zoltan (3x), Drasko, Milan (3x), Sukhareva, Evgeniya (3x), Crouch, Colin S (3x)

7…Nc6 — 6.3% (23 parties)

Ambassadeurs : Bousios, Hristos (2x), Skembris, Spyridon (2x), Kozul, Zdenko (2x), Marjanovic, Slavoljub (1x), Mann, Derek (1x), Morrison, John Stuart (1x), Dizdar, Goran (1x), Covic, Darko (1x)

7…cxd4 — 4.1% (15 parties)

Ambassadeurs : Andersson, Ulf (1x), Petrosian, Tigran V. (1x), Kozul, Zdenko (1x), Mikhalchishin, Adrian (1x), Razmyslov, Alexander (1x), Gorbunov, Pavel (1x), Poetter, Clemens, Dr. (1x), Bachmann, Karlheinz (1x)

7…Nbd7 — 3.0% (11 parties)

Ambassadeurs : Gendron, Bernard (1x), Bolduc, Steve (1x), Casimiro Gabriel Luanda (1x), Xu, Jun (1x), Dizdar, Goran (1x), Valenta, Vit (1x), Bratanov, Zsivko (1x), Bouvier, Bruno (1x)

Analyse statistique des coups candidats

Répartition par niveau Elo (% des parties)

Tranche Elo	N parties	7…b5	7…Nc6	7…cxd4	7…Nbd7
<1800	15	93%	—	—	—
1800-2200	101	84%	8%	1%	2%
2200-2600	225	84%	5%	5%	3%
2600+	6	50%	33%	—	17%

Évolution par décennie (% des parties)

Décennie	N parties	7…b5	7…Nc6	7…cxd4	7…Nbd7
1960s	1	100%	—	—	—
1970s	4	75%	—	25%	—
1980s	24	79%	12%	—	4%
1990s	87	85%	2%	6%	2%
2000s	104	83%	8%	3%	3%
2010s	102	89%	7%	2%	1%
2020s	44	70%	7%	9%	9%

Tendances récentes (2010s → 2020s)

Coup	2010s	2020s	Δ
7…b5	89%	70%	▼ -18.8%
7…Nc6	7%	7%	-0.0%
7…cxd4	2%	9%	▲ +7.1%
7…Nbd7	1%	9%	▲ +8.1%

Parties historiques

7…b5 — 83.3% (305 parties)

1960 — Letelier Martner, Rene vs Bazan, Osvaldo — 1/2-1/2 — Mar del Plata ARG
1971 — Diesen, Carl E vs Bills, William — 1-0 — Ventura
1979 — Miles, Anthony J vs Ribli, Zoltan — 1-0 — Riga izt
1979 — Miles, Anthony J vs Ribli, Zoltan — 0-1 — Riga LAT
1980 — Spiridonov, Nikola vs Djuric, Stefan — 0-1 — Sombor

7…Nc6 — 6.3% (23 parties)

1988 — Bousios, Hristos vs Skembris, Spyridon — 1/2-1/2 — ?
1988 — Bousios, Hristos vs Skembris, Spyridon — 1/2-1/2 — Athens GRE
1989 — Kozul, Zdenko vs Marjanovic, Slavoljub — 1-0 — Zlatibor
1995 — Dizdar, Goran vs Covic, Darko — 1-0 — Zadar CRO
1997 — Mann, Derek vs Morrison, John Stuart — 1-0 — Match

7…cxd4 — 4.1% (15 parties)

1979 — Andersson, Ulf vs Petrosian, Tigran V. — 1/2-1/2 — Buenos Aires ARG
1990 — Morales J., David Alejandro vs ? — 0-1 — Zaragoza
1991 — Razmyslov, Alexander vs Gorbunov, Pavel — 1/2-1/2 — UKR-chT Simferopol UKR
1996 — Kozul, Zdenko vs Mikhalchishin, Adrian — 1-0 — Bled Tch-SLO
1996 — Bukic, Enver vs Marinsek, Tomaz — 1/2-1/2 — Ljubljana

7…Nbd7 — 3.0% (11 parties)

1985 — Gendron, Bernard vs Bolduc, Steve — 1/2-1/2 — Quebec ch Reserve
1995 — Dizdar, Goran vs Valenta, Vit — 1-0 — Graz AUT
1997 — Casimiro Gabriel Luanda vs Xu, Jun — 0-1 — Bad Homburg GER
2000 — Lyrberg, Patrik vs Kallio, Heikki — 1-0 — Jyvaskyla FIN
2001 — Bratanov, Zsivko vs Bouvier, Bruno — 1-0 — Creon VI op