Symmetrical Defense

{{Infobox chess opening

|openingname = Symmetrical Defense

|image = {{Chess diagram||

|rd|nd|bd|qd|kd|bd|nd|rd

|pd|pd| | |pd|pd|pd|pd

| | | | | | | |

| | |pd|pd| | | |

| | |pl|pl| | | |

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|pl|pl| | |pl|pl|pl|pl

|rl|nl|bl|ql|kl|bl|nl|rl

}}

|moves =1.d4 d5 2.c4 c5

|ECO =D06

|birth =1604, Alessandro Salvio

|nameorigin = Austria

|parentopening = Queen's Gambit

|AKA = Austrian Defense

|chessgid =887543&move=3&moves=d4.d5.c4.c5.c5&nodes=10703.75972.75973.887543

}}

The Symmetrical Defense (or Austrian Defense) is a chess opening that begins with the moves:

:1. d4 d5

:2. c4 c5

First described in print by Alessandro Salvio in 1604, the opening is often called the Austrian Defense because it was studied by Austrian chess players including Hans Haberditz (c. 1901–57), Hans Müller (1896–1971), and GM Ernst Grünfeld.{{citation | last1=Hooper | first1=David | author1-link=David Vincent Hooper | last2=Whyld |first2=Kenneth | author2-link=Kenneth Whyld | title=The Oxford Companion to Chess | publisher=Oxford University | year=1996 | isbn=0-19-280049-3 | chapter=Austrian Defence}}

The Symmetrical Defense is an uncommon variation of the Queen's Gambit Declined.

It poses the purest test of Queen's Gambit theory—whether Black can equalize by simply copying White's moves.

Most opening theoreticians believe that White should gain the advantage

and at best Black is playing for a draw.{{citation | last=Korn | first=Walter | author-link=Walter Korn | title=Modern Chess Openings | edition=Twelfth | publisher=David McKay | year=1982 | isbn=0-679-13500-6 | chapter=Queen's Gambit Declined | page=266}}

Grandmaster Hikaru Nakamura employed the unusual opening a few times in 2023 and 2024. With the opening, he drew former world champion Magnus Carlsen in the Champions Chess Tour 2023 finals and beat reining world champion Ding Liren in Norway Chess 2024.{{cite web |author=Anthony Levin |title=Carlsen Beats World Numbers 2 And 3 Back To Back|url=https://www.chess.com/news/view/2023-champions-chess-tour-finals-rr-day-2|website=Chess.com |date=11 December 2023}}{{cite web |author=Colin McGourty|title=Nakamura Crosses 2800, World No. 2 As Carlsen, Praggnanandhaa Also Win|url=https://www.chess.com/news/view/2024-norway-chess-round-5|website=Chess.com |date=1 June 2024}} He employed a similar opening in the Candidates Tournament 2024, beating R Praggnanandhaa with the black pieces in a game beginning with 1.d4 d5 2.Nf3 Nf6 3.c4 c5.{{cite web |author=Anthony Levin|title=Nepomniachtchi, Tan Regain Sole Lead, Nakamura Beats Praggnanandhaa|url=https://www.chess.com/news/view/2024-fide-candidates-tournament-round-11|website=Chess.com |date=18 April 2024}} Nakamura defeated Luca Moroni and drew against Bogdan-Daniel Deac with the opening in the 2024 World Rapid Chess Championship.{{cite web|title=World Rapid Championship (2024) (games of Hikaru Nakamura)|url=https://www.chessgames.com/perl/chess.pl?tid=132349&pid=10084}}

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