Misplaced Pages

Two Knights Defense: Difference between revisions

Article snapshot taken from Wikipedia with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.
Browse history interactively← Previous editNext edit →Content deleted Content addedVisualWikitext
Revision as of 16:03, 4 January 2015 editFrietjes (talk | contribs)Autopatrolled, Extended confirmed users, Template editors1,001,183 editsNo edit summary← Previous edit Revision as of 08:43, 5 January 2015 edit undoIoannes Pragensis (talk | contribs)Autopatrolled, Extended confirmed users7,586 edits 4...Bc5!?: title etc.Next edit →
Line 56: Line 56:
4...Nxe4?! must be handled carefully:<ref>Harding/Botterill (1977), p. 66</ref> 5.Bxf7+! (5.Nxf7? Qh4! 6.g3 Qh3 7.Nxh8 Qg2 8.Rf1 Nd4 9.Qh5+ g6 10.Nxg6 hxg6 11.Qxg6+ Kd8) 5...Ke7 6.d4! d5 (6...h6 7.Nxe4 Kxf7 and now either 8.dxe5 Qe8 9.f4 d6 10.0-0 or 8.d5 Ne7 9.Qh5+ g6 10.Qxe5 give White the advantage) 7.Nc3! (best, discovered by Soviet player Lopukhin) Nxc3 8.bxc3 Qd6 (8...Bf5 9.Qf3±; 8...e4 9.f3!) 9.a4! Kd8 10.Bg8! (Estrin) Ke8 11.Bxh7 and White has the edge (]). 4...Nxe4?! must be handled carefully:<ref>Harding/Botterill (1977), p. 66</ref> 5.Bxf7+! (5.Nxf7? Qh4! 6.g3 Qh3 7.Nxh8 Qg2 8.Rf1 Nd4 9.Qh5+ g6 10.Nxg6 hxg6 11.Qxg6+ Kd8) 5...Ke7 6.d4! d5 (6...h6 7.Nxe4 Kxf7 and now either 8.dxe5 Qe8 9.f4 d6 10.0-0 or 8.d5 Ne7 9.Qh5+ g6 10.Qxe5 give White the advantage) 7.Nc3! (best, discovered by Soviet player Lopukhin) Nxc3 8.bxc3 Qd6 (8...Bf5 9.Qf3±; 8...e4 9.f3!) 9.a4! Kd8 10.Bg8! (Estrin) Ke8 11.Bxh7 and White has the edge (]).


====4...Bc5!?==== ====4...Bc5 (Traxler Variation or Wilkes-Barre Variation)====
] ] ] played 4...Bc5!? in Reinisch–Traxler, ] 1896. Some decades later, several Pennsylvania chess amateurs, (mainly K. Williams) analyzed the variation and decided to name it after their hometown ], so today 4...Bc5 is known as both the Traxler Variation and (in the U.S.A. and the United Kingdom<ref>{{Cite web | last =Elburg | first =John | title =New in Chess Year book issue 65 | work =Chessbook Reviews | publisher =Chess Books | year =2002 | url =http://chessbooks.nl/elburg59.html | accessdate =2010-04-30 }}</ref> only) the Wilkes-Barre Variation. This bold move ignores White's attack on f7 and leads to wild play where a number of long variations have been analyzed to a ] by ]. White can play 5.d4, 5.Nxf7, or 5.Bxf7+. After 5.d4 d5!, White's best is to go into an equal endgame after 6.dxc5 dxc4 7.Qxd8+. Other sixth moves have scored very badly for White. The usual move used to be 5.Nxf7, but this is very complicated after 5...Bxf2+. The current main lines all are thought to lead to drawn or equal positions, e.g. after 6.Kxf2 Nxe4+ 7.Kg1, or even 7.Ke3. In the year 2000, this last move (which was already considered by Traxler himself) was credited as the 'refutation' of the Traxler variation, after an article in the ''New in Chess Yearbook'' series, featuring a cover diagram after White's seventh move. However, computer analysis subsequently showed that Black can probably force a draw after this move as well. White's best try for an advantage is probably 5.Bxf7+ Ke7 6.Bb3 (although 6.Bd5 was the move recommended by ] in his recent Fritztrainer DVD),<ref name=LT>http://chessbase-shop.com/en/products/two_knight%E2%80%98s_defence</ref> as this poses Black the most problems. No grandmasters have regularly adopted the Wilkes-Barre as Black, but ] and ] have played it occasionally even in top competition. No clear refutation is known. ] ] ] played the extremely sharp 4...Bc5 in Reinisch–Traxler, ] 1896. Some decades later, several Pennsylvania chess amateurs, (mainly K. Williams) analyzed the variation and decided to name it after their hometown ], so today 4...Bc5 is known as both the Traxler Variation and (in the U.S.A. and the United Kingdom<ref>{{Cite web | last =Elburg | first =John | title =New in Chess Year book issue 65 | work =Chessbook Reviews | publisher =Chess Books | year =2002 | url =http://chessbooks.nl/elburg59.html | accessdate =2010-04-30 }}</ref> only) the Wilkes-Barre Variation.
This bold move ignores White's attack on f7 and leads to wild play where a number of long variations have been analyzed to a ] by ].
White can play 5.d4, 5.Nxf7, or 5.Bxf7+. After 5.d4 d5!, White's best is to go into an equal endgame after 6.dxc5 dxc4 7.Qxd8+. Other sixth moves have scored very badly for White.
The usual move used to be 5.Nxf7, but this is very complicated after 5...Bxf2+. The current main lines all are thought to lead to drawn or equal positions, e.g. after 6.Kxf2 Nxe4+ 7.Kg1, or even 7.Ke3. In the year 2000, this last move (which was already considered by Traxler himself) was credited as the 'refutation' of the Traxler variation, after an article in the ''New in Chess Yearbook'' series, featuring a cover diagram after White's seventh move. However, computer analysis subsequently showed that Black can probably force a draw after this move as well.
White's best try for an advantage is probably 5.Bxf7+ Ke7 6.Bb3 (although 6.Bd5 was the move recommended by ] in his recent Fritztrainer DVD),<ref name=LT>http://chessbase-shop.com/en/products/two_knight%E2%80%98s_defence</ref> as this poses Black the most problems. No grandmasters have regularly adopted the Wilkes-Barre as Black, but ] and ] have played it occasionally even in top competition. No clear refutation is known.


====4...d5 (the main line)==== ====4...d5 (the main line)====

Revision as of 08:43, 5 January 2015

Chess opening
Two Knights Defense
abcdefgh
8a8 black rookc8 black bishopd8 black queene8 black kingf8 black bishoph8 black rooka7 black pawnb7 black pawnc7 black pawnd7 black pawnf7 black pawng7 black pawnh7 black pawnc6 black knightf6 black knighte5 black pawnc4 white bishope4 white pawnf3 white knighta2 white pawnb2 white pawnc2 white pawnd2 white pawnf2 white pawng2 white pawnh2 white pawna1 white rookb1 white knightc1 white bishopd1 white queene1 white kingh1 white rook8
77
66
55
44
33
22
11
abcdefgh
Moves1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6
ECOC55–C59
OriginLate 16th century
ParentItalian Game

The Two Knights Defense is a chess opening that begins with the moves:

1. e4 e5
2. Nf3 Nc6
3. Bc4 Nf6

First recorded by Polerio (c. 1550 – c. 1610) in the late 16th century, this line of the Italian Game was extensively developed in the 19th century. Black's third move is a more aggressive defense than the Giuoco Piano which would result from 3...Bc5. In fact, David Bronstein suggested that the term "defense" does not fit, and that the name "Chigorin Counterattack" would be more appropriate. The Two Knights has been adopted as Black by many aggressive players including Mikhail Chigorin and Paul Keres, and World Champions Mikhail Tal and Boris Spassky. The theory of this opening has been explored extensively in correspondence chess by players such as Hans Berliner and Yakov Estrin.

This article uses algebraic notation to describe chess moves.

Main variations

4.Ng5

Siegbert Tarrasch called 4.Ng5 a "duffer's move" (ein richtiger Stümperzug) and Panov called it "primitive", but this attack on f7 practically wins a pawn by force. Despite Tarrasch's criticism, many players consider 4.Ng5 White's best chance for an advantage and it has been played by World Champions Wilhelm Steinitz, Bobby Fischer, Anatoly Karpov, Garry Kasparov, and Viswanathan Anand.

4...Nxe4?!

4...Nxe4?! must be handled carefully: 5.Bxf7+! (5.Nxf7? Qh4! 6.g3 Qh3 7.Nxh8 Qg2 8.Rf1 Nd4 9.Qh5+ g6 10.Nxg6 hxg6 11.Qxg6+ Kd8) 5...Ke7 6.d4! d5 (6...h6 7.Nxe4 Kxf7 and now either 8.dxe5 Qe8 9.f4 d6 10.0-0 or 8.d5 Ne7 9.Qh5+ g6 10.Qxe5 give White the advantage) 7.Nc3! (best, discovered by Soviet player Lopukhin) Nxc3 8.bxc3 Qd6 (8...Bf5 9.Qf3±; 8...e4 9.f3!) 9.a4! Kd8 10.Bg8! (Estrin) Ke8 11.Bxh7 and White has the edge (Gligorić).

4...Bc5 (Traxler Variation or Wilkes-Barre Variation)

Czech problemist Karel Traxler played the extremely sharp 4...Bc5 in Reinisch–Traxler, Hostouň 1896. Some decades later, several Pennsylvania chess amateurs, (mainly K. Williams) analyzed the variation and decided to name it after their hometown Wilkes-Barre, Pennsylvania, so today 4...Bc5 is known as both the Traxler Variation and (in the U.S.A. and the United Kingdom only) the Wilkes-Barre Variation.

This bold move ignores White's attack on f7 and leads to wild play where a number of long variations have been analyzed to a draw by perpetual check.

White can play 5.d4, 5.Nxf7, or 5.Bxf7+. After 5.d4 d5!, White's best is to go into an equal endgame after 6.dxc5 dxc4 7.Qxd8+. Other sixth moves have scored very badly for White.

The usual move used to be 5.Nxf7, but this is very complicated after 5...Bxf2+. The current main lines all are thought to lead to drawn or equal positions, e.g. after 6.Kxf2 Nxe4+ 7.Kg1, or even 7.Ke3. In the year 2000, this last move (which was already considered by Traxler himself) was credited as the 'refutation' of the Traxler variation, after an article in the New in Chess Yearbook series, featuring a cover diagram after White's seventh move. However, computer analysis subsequently showed that Black can probably force a draw after this move as well.

White's best try for an advantage is probably 5.Bxf7+ Ke7 6.Bb3 (although 6.Bd5 was the move recommended by Lawrence Trent in his recent Fritztrainer DVD), as this poses Black the most problems. No grandmasters have regularly adopted the Wilkes-Barre as Black, but Alexander Beliavsky and Alexei Shirov have played it occasionally even in top competition. No clear refutation is known.

4...d5 (the main line)

After 4... d5 White has little option but to play 5. exd5, since both the bishop and e4 pawn are attacked. Then Black usually plays 5... Na5 but there are other options:

  • The recapture 5...Nxd5?! is very risky. Albert Pinkus tried to bolster this move with analysis in 1943 and 1944 issues of Chess Review, but White gets a strong attack with either the safe Lolli Variation 6.d4! or the sacrificial Fried Liver (or Fegatello) Attack 6.Nxf7!? Kxf7 7.Qf3+ Ke6 8.Nc3. These variations are usually considered too difficult for Black to defend over the board, but they are sometimes used in correspondence play. Lawrence Trent describes 5...Nxd5 as "a well-known bad move" (or words to that effect).
  • The Fritz Variation 5...Nd4, and Ulvestad's Variation 5...b5, are related as they share a common subvariation. American master Olav Ulvestad introduced 5...b5 in a 1941 article in Chess Review. White has only one good reply: 6.Bf1!, protecting g2 so White can answer 6...Qxd5? with 7.Nc3. Both 6.Bxb5 Qxd5 7.Bxc6 Qxc6 and 6.dxc6 bxc4 7.Nc3 are weak. Black's best response is to transpose to the Fritz Variation with 6...Nd4, making another advantage of 6.Bf1 apparent—the bishop is not attacked as it would be if White had played 6.Be2. German master Alexander Fritz (1857–1932) suggested 5...Nd4 to Carl Schlechter, who wrote about the idea in a 1904 issue of Deutsche Schachzeitung. In 1907 Fritz himself wrote an article about his move in the Swedish journal Tidskrift för Schack. White's best reply is 6.c3, when the game often continues 6...b5 7.Bf1 Nxd5 8.Ne4 or 8.h4.
abcdefgh
8a8 black rookc8 black bishopd8 black queene8 black kingh8 black rooka7 black pawnf7 black pawng7 black pawnc6 black pawnd6 black bishopf6 black knighth6 black pawna5 black knighte5 white knighte4 black pawna2 white pawnb2 white pawnc2 white pawnd2 white pawne2 white bishopf2 white pawng2 white pawnh2 white pawna1 white rookb1 white knightc1 white bishopd1 white queene1 white kingh1 white rook8
77
66
55
44
33
22
11
abcdefgh
Main line of Two Knights Defense

After 5...Na5, Paul Morphy would play to hold the gambit pawn with 6.d3. The Morphy Variation (or Kieseritzky Attack) has not been popular, since it has long been known that Black obtains good chances for the pawn with 6...h6 7.Nf3 e4 8.Qe2 Nxc4 9.dxc4 Bc5. (Bronstein once tried the piece sacrifice 8.dxe4!? with success, but its soundness is doubtful.) Instead, White usually plays 6.Bb5+, when play almost always continues 6...c6 7.dxc6 bxc6 8.Be2 h6. (The move 8.Qf3?!, popular in the nineteenth century and revived by Efim Bogoljubov in the twentieth, is still played occasionally, but Black obtains a strong attack after either 8...h6!, 8...Rb8, or 8...Be7) White then has a choice of retreats for the knight. The usual move here is 9.Nf3, after which Black obtains some initiative after 9...e4 10.Ne5 Bd6 (see diagram; this is considered to be the main line of the Two Knights Defense). 10...Bc5 is a viable alternative for Black. Steinitz favored 9.Nh3 instead, although it did not bring him success in his famous 1891 cable match against Chigorin. The Steinitz Variation was mostly forgotten until Fischer revived it in the 1960s. Nigel Short led a second revival of 9.Nh3 in the 1990s, and today it is thought to be about equal in strength to the more common 9.Nf3. In addition to the moves 8.Be2 and 8.Qf3, the move 8.Bd3 is a valid alternative that has apparently become quite "fashionable" or "trendy" in recent years. Also note that after 5...Na5 6.Bb5+, the reply 6...Bd7 by Black is a valid idea that has been explored.

4.Nc3

The attempt to defend the pawn with 4.Nc3 does not work well since Black can take the pawn anyway and use a fork trick to regain the piece, 4.Nc3?! Nxe4! 5.Nxe4 d5. The try 5.Bxf7+? does not help, as Black has the bishop pair and a better position after 5...Kxf7 6.Nxe4 d5. Instead, 4.Nc3 is usually played with the intent to gambit the e-pawn with the Boden–Kieseritzky Gambit, 4.Nc3 Nxe4 5.0-0. This gambit is not commonly seen in tournament play as it is not well regarded by opening theory, but it can offer White good practical chances, especially in blitz chess.

4.d3

The quiet move 4.d3 transposes into the Giuoco Pianissimo if Black responds 4...Bc5, but there are also independent variations after 4...Be7 or 4...h6. White tries to avoid the tactical battles that are common in other lines of the Two Knights and to enter a more positional game. The resulting positions take on some characteristics of the Ruy Lopez if White plays c3 and retreats the bishop to c2 via Bc4–b3–c2. This move became popular in the 1980s and has been used by John Nunn and others. Black can confound White's attempt to avoid tactical play with 4...d5!?. This move is rarely played as opening theory does not approve, but Jan Piński suggests that it is better than is commonly believed.

4.d4

White can choose to develop rapidly with 4.d4 exd4 5.0-0. Now Black can equalize simply by eliminating White's last center pawn with 5...Nxe4, after which White regains the material with 6.Re1 d5 7.Bxd5 Qxd5 8.Nc3 but Black has a comfortable position after 8...Qa5 or 8...Qh5, or obtain good chances with the complex Max Lange Attack after 5...Bc5 6.e5 d5. The extensively analyzed Max Lange can also arise from the Giuoco Piano or Scotch Game. White can choose to avoid these lines by playing 5.e5, a line often adopted by Sveshnikov. After 5.e5, either 5...Ne4 or 5...Ng4 is a playable reply, but most common and natural is 5...d5 6.Bb5 Ne4 7.Nxd4 Bc5, with sharp play. The tricky 5.Ng5?! is best met by 5...d5! 6.exd5 Qe7+!.

COTT

abcdefgh
8a8 black rookc8 black bishopd8 black queene8 black kingf8 black bishoph8 black rooka7 black pawnb7 black pawnc7 black pawnd7 black pawnf7 black pawng7 black pawnh7 black pawnc6 black knighte5 black pawnc4 white bishope4 black knightc3 white knightf3 white knighta2 white pawnb2 white pawnc2 white pawnd2 white pawnf2 white pawng2 white pawnh2 white pawna1 white rookc1 white bishopd1 white queenf1 white rookg1 white king8
77
66
55
44
33
22
11
abcdefgh
Boden–Kieseritzky Gambit
abcdefgh
8a8 black rookc8 black bishopd8 black queene8 black kingh8 black rooka7 black pawnb7 black pawnc7 black pawnf7 black pawng7 black pawnh7 black pawnc6 black knightf6 black knightc5 black bishopd5 black pawne5 white pawnc4 white bishopd4 black pawnf3 white knighta2 white pawnb2 white pawnc2 white pawnf2 white pawng2 white pawnh2 white pawna1 white rookb1 white knightc1 white bishopd1 white queenf1 white rookg1 white king8
77
66
55
44
33
22
11
abcdefgh
Max Lange Attack
abcdefgh
8a8 black rookc8 black bishopd8 black queene8 black kingh8 black rooka7 black pawnb7 black pawnc7 black pawnd7 black pawnf7 black pawng7 black pawnh7 black pawnc6 black knightf6 black knightc5 black bishope5 black pawng5 white knightc4 white bishope4 white pawna2 white pawnb2 white pawnc2 white pawnd2 white pawnf2 white pawng2 white pawnh2 white pawna1 white rookb1 white knightc1 white bishopd1 white queene1 white kingh1 white rook8
77
66
55
44
33
22
11
abcdefgh
Wilkes-Barre or Traxler Variation

White must respond to the attack on his e-pawn (For explanation of notation, see chess opening theory table).

1. e4 e5 2. Nf3 Nc6 3. Bc4 Nf6
4 5 6 7 8 9 10
Wilkes-Barre or Traxler Variation Ng5
Bc5!?
Bxf7+!
Ke7
Bb3!
-
-
-
-
-
-
-
-
-
Lolli Variation ...
d5
exd5
Nxd5!?
d4!
-
-
-
-
-
-
-
-
-
Fried Liver Attack ...
...
...
...
Nxf7!?
Kxf7
Qf3+
Ke6
Nc3
-
-
-
-
-

Morphy Variation ...
...
...
Na5
d3
h6
Nf3
e4
Qe2
Nxc4
dxc4
Bc5
-
-
Main Line ...
...
...
...
Bb5+
c6
dxc6
bxc6
Be2
h6
Nf3
e4
Ne5
-
Steinitz Variation ...
...
...
...
...
...
...
...
...
...
Nh3
-
-
-
Ulvestad Variation ...
...
...
b5
Bf1!
Nd4
c3
Nxd5
Ne4
-
-
-
-
-
Fritz Variation ...
...
...
Nd4
c3
b5
Bf1!
Nxd5
Ne4
-
-
-
-
-
...
Nxe4?!
Bxf7+!
Ke7
d4!
d5
Nc3!
Nxc3
bxc3
Qd6
a4!
Kd8
Bg8!
-
Boden–Kieseritzky Gambit Nc3
Nxe4
0-0
Nxc3
dxc3
Qe7
Ng5
Nd8
-
-
-
-
-
-
Giuoco Pianissimo, by transposition d3
Bc5
-
-
-
-
-
-
-
-
-
-
-
-
3 ...
d5!?
exd5
Nxd5
-
-
-
-
-
-
-
-
-
-
4 ...
Be7
-
-
-
-
-
-
-
-
-
-
-
-
5 d4
exd4
-
-
-
-
-
-
-
-
-
-
-
-
6 ...
...
0-0
Nxe4
Re1
d5
Bxd5
Qxd5
Nc3
-
-
-
-
-
Max Lange Attack ...
...
...
Bc5
e5
d5
exf6
dxc4
Re1+
Be6
Ng5
Qd5
Nc3
Qf5
8 ...
...
e5
d5
Bb5
Ne4
Nxd4
Bc5
-
-
-
-
-
-
9 ...
...
...
Ne4
-
-
-
-
-
-
-
-
-
-
10 ...
...
...
Ng4
-
-
-
-
-
-
-
-
-
-

Notes

  1. Y.Estrin (1983). The Two Knight's Defence. Batsford. ISBN 0-7134-3991-2.
  2. ^ Bronstein, David (1991) . 200 Open Games. Dover. pp. 60–61. ISBN 0-486-26857-8.
  3. Harding/Botterill (1977), p. 66
  4. Elburg, John (2002). "New in Chess Year book issue 65". Chessbook Reviews. Chess Books. Retrieved 2010-04-30.
  5. ^ http://chessbase-shop.com/en/products/two_knight%E2%80%98s_defence
  6. Bronstein–Rojahn, Moscow Olympiad 1956 at chessgames.com

References

Further reading

External links

Categories: