Pirc Defence - AbsoluteAstronomy.com

The Pirc Defence sometimes known as the Ufimtsev Defence or Yugoslav Defence, is a chess opening

Chess opening

A chess opening is the group of initial moves of a chess game. Recognized sequences of opening moves are referred to as openings as initiated by White or defenses, as created in reply by Black. There are many dozens of different openings, and hundreds of named variants. The Oxford Companion to...

characterised by Black responding to 1.e4 with 1...d6 and 2...Nf6, followed by ...g6 and ...Bg7, while allowing White to establish an impressive-looking centre with pawns on d4 and e4. It is named after the Slovenian International Grandmaster Vasja Pirc

Vasja Pirc

Vasja Pirc was a leading Slovenian chess player. His name is most familiar to contemporary players as the originator of the hypermodern Pirc Defense...

General remarks

The Pirc Defence is a relatively new opening; while it was seen on occasion in the late nineteenth century, it was considered irregular, thus remained a sideline. The opening only began gaining some popularity after World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

, and by the 1960s it was regarded as playable, owing in large part to the efforts of Canadian Grandmaster Duncan Suttles

Duncan Suttles

Duncan Suttles is an International Grandmaster of chess who was the strongest Canadian player between the eras of Abe Yanofsky and Kevin Spraggett. He is one of the few over-the-board grandmasters who also holds the title of Grandmaster of Correspondence Chess. Suttles has been inactive in...

. Black, in hypermodern

Hypermodernism (chess)

Hypermodernism is a school of chess that emerged after World War I. It featured challenges on the chess ideologies presented by central European masters, such as on Wilhelm Steinitz’ approach to the centre. It also challenged in particular the dogmatic rules set down by Siegbert Tarrasch...

fashion, does not immediately stake a claim in the centre with pawns

Pawn (chess)

The pawn is the most numerous and weakest piece in the game of chess, historically representing infantry, or more particularly armed peasants or pikemen. Each player begins the game with eight pawns, one on each square of the rank immediately in front of the other pieces...

; rather, he/she works to undermine White's centre from the flanks. Its first appearance in a World Championship match was in 1972, when it was played by Bobby Fischer

Bobby Fischer

Robert James "Bobby" Fischer was an American chess Grandmaster and the 11th World Chess Champion. He is widely considered one of the greatest chess players of all time. Fischer was also a best-selling chess author...

against Boris Spassky

Boris Spassky

Boris Vasilievich Spassky is a Soviet-French chess grandmaster. He was the tenth World Chess Champion, holding the title from late 1969 to 1972...

at Reykjavik

Reykjavík

Reykjavík is the capital and largest city in Iceland.Its latitude at 64°08' N makes it the world's northernmost capital of a sovereign state. It is located in southwestern Iceland, on the southern shore of Faxaflói Bay...

(game 17); the game wound up drawn

Draw (chess)

In chess, a draw is when a game ends in a tie. It is one of the possible outcomes of a game, along with a win for White and a win for Black . Usually, in tournaments a draw is worth a half point to each player, while a win is worth one point to the victor and none to the loser.For the most part,...

.

The most common opening sequence is 1.e4 d6 2.d4 Nf6 3.Nc3 g6. A distinction is usually drawn between the Pirc and lines where Black delays the development of his knight to f6, or omits it altogether; this is known as the Modern or Robatsch Defence. The tenth edition of Modern Chess Openings
Modern Chess Openings
Modern Chess Openings is an important reference book on the chess openings, first published in 1911 by the British players Richard Clewin Griffith and John Herbert White...

(1965) grouped the Pirc and Robatsch together as the "Pirc-Robatsch Defense".

The oldest game with the Pirc Defence in the Chessgames.com database is between Josef Noa

Josef Noa

Joseph Noa was a Hungarian chess master.He was a judge by profession. Although an amateur he played in a number of tournaments throughout the 1880s and 1890s and defeated some of the famous players of his time. In 1880, he took 8th in Graz...

and Amos Burn

Amos Burn

Amos Burn was an English chess player, one of the world's leading players at the end of the 19th century, and a chess writer....

in Frankfurt 1887.

Early deviations

After 1.e4 d6 2.d4 Nf6 3.Nc3, 3...g6 is the main line Pirc. Black has an alternative, known as the Pribyl System or Czech Defence, which begins with 3...c6, which often transposes to the Pirc if Black later plays ...g6. Alternatively, Black can play ...Qa5 and ...e5 to challenge White's centre, or expand on the queenside with ...b5.

An unusual but quite reasonable deviation for White is 1.e4 d6 2.d4 Nf6 3.f3. At the 1989 Barcelona

Barcelona

Barcelona is the second largest city in Spain after Madrid, and the capital of Catalonia, with a population of 1,621,537 within its administrative limits on a land area of...

World Cup event, former world champion Garry Kasparov

Garry Kasparov

Garry Kimovich Kasparov is a Russian chess grandmaster, a former World Chess Champion, writer, political activist, and one of the greatest chess players of all time....

surprised American Grandmaster Yasser Seirawan with this move. After 3...g6 4.c4, an unhappy Seirawan found himself defending the King's Indian Defence

King's Indian Defence

The King's Indian Defence is a common chess opening. It arises after the moves:Black intends to follow up with 3...Bg7 and 4...d6.The Grünfeld Defence arises when Black plays 3...d5 instead, and is considered a separate opening...

for the first time in his life, though he managed to draw the game. Black can avoid a King's Indian with 3...e5, which may lead to an Old Indian

Old Indian Defense

The Old Indian Defense is a chess opening defined by the moves:This opening is distinguished from the King's Indian Defense by Black developing his king's bishop on e7 rather than fianchettoing it at g7...

type of position after 4.d5, or with 3...d5. This can transpose to the Classical Variation of the French Defence

French Defence

The French Defence is a chess opening. It is characterised by the moves:The French has a reputation for solidity and resilience, though it can result in a somewhat cramped game for Black in the early stages...

after 4.e5 Nfd7 5.f4 e6 6.Nf3, to the Tarrasch Variation of the French Defence after 4.e5 Nfd7 5.f4 e6 6.c3 c5 7.Nd2 Nc6 8.Ndf3, or even to the Blackmar-Diemer Gambit

Blackmar-Diemer Gambit

The Blackmar–Diemer Gambit is a chess opening characterized by the moves:- History :The Blackmar–Diemer Gambit arose as a development of the earlier Blackmar Gambit, named after Armand Blackmar, a relatively little-known New Orleans player of the late 19th century who popularized its...

with an extra tempo

Tempo

In musical terminology, tempo is the speed or pace of a given piece. Tempo is a crucial element of any musical composition, as it can affect the mood and difficulty of a piece.-Measuring tempo:...

for White after 4.Nc3 dxe4 5.Bg5 exf3 6.Nxf3.

A common deviation by Black in recent practice is 1.e4 d6 2.d4 Nf6 3.Nc3 e5. This has been tried by many GMs over the years, including Zurab Azmaiparashvili

Zurab Azmaiparashvili

Zurab Azmaiparashvili is a chess Grandmaster from Georgia. In the September 2010 FIDE list, he has an Elo rating of 2637, making him 114th in the world and Georgia's number two.-Career:He became a Grandmaster in 1988...

and Christian Bauer

Christian Bauer

Christian Bauer is a French chess player and author. In 1996 he won the French Chess Championship. In 2009 he came first at Vicente Bonil ahead of 21 GMs and 33 titled players.-External links:...

. White's 4.dxe5 is known to be equal, and play normally continues 4...dxe5 5.Qxd8+ Kxd8 6.Bc4 Be6 7.Bxe6 fxe6. Instead, White normally transposes

Transposition (chess)

A transposition in chess is a sequence of moves that results in a position which may also be reached by another, more common sequence of moves. Transpositions are particularly common in opening, where a given position may be reached by different sequences of moves...

to the Philidor Defence

Philidor Defence

The Philidor Defence is a chess opening characterised by the moves:It is named after the famous 18th-century player François-André Danican Philidor, who advocated it as an alternative to the common 2...Nc6...

with 4.Nf3.

Austrian Attack

The Austrian Attack begins 1.e4 d6 2.d4 Nf6 3.Nc3 g6 4.f4 Bg7 5.Nf3, and was a favourite of Fischer. It is also well respected by Nick de Firmian

Nick de Firmian

Nicholas Ernest de Firmian , is a chess grandmaster and three-time U.S. chess champion, winning in 1987 , 1995, and 1998. He also tied for first in 2002, but Larry Christiansen won the playoff...

, the author of Modern Chess Openings

Modern Chess Openings

Modern Chess Openings is an important reference book on the chess openings, first published in 1911 by the British players Richard Clewin Griffith and John Herbert White...

(MCO). In placing pawns on d4, e4 and f4, White establishes a powerful centre, intending to push in the centre and/or attack on the kingside; in the main line, Black will usually counter with ....e5, aiming for play against the dark squares and weaknesses created by White's central advance. This direct, aggressive line is one of the most ambitious systems against the Pirc. Jan Timman

Jan Timman

Jan Timman is a Dutch chess Grandmaster who was one of the world's leading players from the late 1970s to the early 1990s. At the peak of his career he was considered to be the best non-Soviet player and was known as "The Best of the West"...

has played the Austrian successfully with both colours. Yuri Balashov

Yuri Balashov

-Chess career:He was awarded the grandmaster title in 1973. Balashov was Moscow Champion in 1970 and 2nd to Anatoly Karpov in the 1976 USSR Chess Championship. In 1977 he won Lithuanian Chess Championship. He finished 1st= at Lone Pine 1977 and 1st= at Wijk aan Zee 1982.Balashov represented the...

does well with the White pieces, and Valery Beim has an impressive score on the Black side.

5....0-0

The most frequently played variation of this after 5....0-0 is the Weiss Variation, 6.Bd3, with 6....Nc6 the most common response. 6.e5 is a sharp try, with unclear consequences, which was much played in the 1960s, though it has never attained popularity at the highest levels. 6.Be2 is another move which was often seen in the 1950s and early 1960s, though the defeat sustained by Fischer in the game given below, at the hands of Korchnoi

Viktor Korchnoi

Viktor Lvovich Korchnoi ; pronounced in the original Russian as "karch NOY"; Ви́ктор Льво́вич Корчно́й, born March 23, 1931 is a professional chess player, author and currently the oldest active grandmaster on the tournament circuit...

, spurred White players, including Fischer himself, to turn to 6.Bd3. In the 1980s, 6.Be2 c5 7.dxc5 Qa5 8.0-0 Qxc5+ 9.Kh1 was revived. 6.Be3 is another possibility, explored in the 1970s.

5....c5

Black's chief alternative to 5....0-0 lies in an immediate strike against the White centre with 5....c5, to which the usual response is either 6.dxc5 or 6.Bb5+. The former allows 6... Qa5. The latter promises a tactical melee, with a common line being 6.Bb5+ Bd7 7.e5 Ng4 8.e6 (8.h3 or 8.Bxd7+ are other possibilities) fxe6, which was thought bad, until Yasser Seirawan played the move against Gyula Sax

Gyula Sax

Gyula Sax is a Hungarian chess player and International Arbiter , born in Budapest.He was awarded the IM title in 1972 and the GM title in 1974. He was the Hungarian Chess Champion in 1976 and 1977 . In 1971-72, he was the European Junior Champion, and he placed first at Rovinj-Zagreb 1975,...

in 1988 (8... Bxb5 is the alternative, if Black does not want the forced draw in the main line) 9.Ng5 Bxb5!

Now if White tries 10.Nxe6, Black has 10....Bxd4!, ignoring the threat to his queen, in view of 11.Nxd8 Bf2+ 12.Kd2 Be3+ with a draw by perpetual check. White can instead try 11.Nxb5, with complicated play.

White can also essay the sharp 6.e5 against 5....c5, after which 6....Nfd7 7.exd6 0-0 is considered to offer good play for Black.

Classical (Two Knights) System

The Classical (Two Knights) System begins 1.e4 d6 2.d4 Nf6 3.Nc3 g6 4.Nf3 Bg7 5.Be2 0-0 6.0-0. White contents himself with the 'classical' pawn centre with pawns at e4 and d4, forgoing the committal move f2-f4 as Black castles

Castling

Castling is a special move in the game of chess involving the king and either of the original rooks of the same color. It is the only move in chess in which a player moves two pieces at the same time. Castling consists of moving the king two squares towards a rook on the player's first rank, then...

and builds a compact structure. Efim Geller

Efim Geller

Efim Petrovich Geller was a Soviet chess player and world-class grandmaster at his peak. He won the Soviet Championship twice and was a Candidate for the World Championship on six occasions...

, Anatoly Karpov

Anatoly Karpov

Anatoly Yevgenyevich Karpov is a Russian chess grandmaster and former World Champion. He was the official world champion from 1975 to 1985 when he was defeated by Garry Kasparov. He played three matches against Kasparov for the title from 1986 to 1990, before becoming FIDE World Champion once...

and Evgeni Vasiukov

Evgeni Vasiukov

Evgeni Andreyevich Vasiukov is a Russian chess Grandmaster. During his career, he won the Championship of Moscow on six occasions and scored many victories in international tournaments, such as Belgrade Open 1961, Moscow International 1961, East Berlin 1962, and Manila 1974...

have all successfully used this system for White; Zurab Azmaiparashvili

Zurab Azmaiparashvili

has scored well as Black. The most common responses for Black are 6....Bg4, 6....c6 or 6....Nc6, with 6....Bg4 the main line from the mid-1960s onwards.

150 Attack and Argentinian Attack

The setup f2-f3, Be3 and Qd2 is commonly used against the King's Indian Defence and Dragon Sicilian, and can also be used against the Pirc; indeed, this system is as old as the Pirc itself.

The system 4.f3 was introduced by Argentine players around 1930 and again in 1950. It was never considered dangerous for Black because of 4.f3 Bg7 5.Be3 c6 6.Qd2 b5. It received a severe blow around 1985, when Gennady Zaichik showed that Black could castle anyway and play a dangerous gambit with 5...0-0 6.Qd2 e5.

The Argentines feared the sally ...Ng4, though some British players (especially Mark Hebden

Mark Hebden

Mark Hebden is an English chess player who holds the title Grandmaster.Hebden was British Rapidplay Chess Champion in 1990, 1994, 2001, 2005 and 2009....

, Paul Motwani

Paul Motwani

Paul Motwani is of Scottish/Indian descent and was Scotland's first chess Grandmaster . Born in Glasgow but growing up in Dundee , he became World Cadet Champion in 1978, and won the first of his seven Scottish Championship titles that year...

, Gary Lane

Gary Lane

Gary William Lane is a professional chess player and author. He became an International Master in 1987 and won the Commonwealth Chess Championship in 1988...

, later also Michael Adams) came to realise that this was mainly dangerous for Black, therefore playing Be3 and Qd2 in all sorts of move orders, whilst omitting f2-f3. They called this the 150 Attack, because only players of this strength (about ELO

Elo rating system

The Elo rating system is a method for calculating the relative skill levels of players in two-player games such as chess. It is named after its creator Arpad Elo, a Hungarian-born American physics professor....

1800) could be naive enough to expect mate in 25 moves.

The original Argentinian idea probably is only viable after 4.Be3 Bg7 5.Qd2 0-0 6.0-0-0 c6 (or Nc6) 7.f3 b5 8.h4. Black usually does not castle though and prefers 5...c6 or even 4...c6. The question of whether and when to insert Nf3 remains open.

Other systems

4.Bg5 was introduced by Robert Byrne in the 1960s, after which Black has often played the natural 4....Bg7, though 4....c6 is considered more flexible, as Black may wish to save a tempo in anticipation of White's plan of Qd2, followed by Bh6, by deferring ....Bg7 as long as possible, playing for queenside activity with ....b7-b5 and ....Qa5. White's idea of Qd2 and Bh6 may give a transposition to the lines with Be3 and Qd2. A less common method of playing this system is 4.Nf3 Bg7 5.Bg5.

4.Bc4 Bg7 5.Qe2 is a sharp try for advantage; 5....Nc6 can lead to hair-raising complications after 6.e5, when Black's best line may be 6....Ng4 7.e6 Nxd4 8.Qxg4 Nxc2+, avoiding the more frequently played 6....Nxd4 7.exf6 Nxe2 8.fxg7 Rg8 9.Ngxe2 Rxg7, which has been generally considered to lead to an equal or unclear position, though White has scored heavily in practice. Another possibility for Black is 5....c6, though 6.e5 dxe5 7.dxe5 Nd5 8.Bd2, followed by long castling, gives White the advantage, as Black's position is cramped and he lacks active counterplay. 6... Nd7 is now considered fine for Black, in view of 7. e6?! fxe6 8. Qxe6 Nde5! 9. Qd5 e6 with advantage to Black. If White instead plays the better 7.Nf3, Black has multiple solid choices, including ...O-O and ...Nb6 (followed by Na5), which is considered to equalise.

4.g3 and 5.Bg2, followed by Nge2, is a solid line, which was sometimes adopted by Karpov

Anatoly Karpov

Sample games

In the following game, Azmaiparashvili uses the Pirc to defeat reigning world champion

World Chess Championship

The World Chess Championship is played to determine the World Champion in the board game chess. Men and women of any age are eligible to contest this title....

Karpov:

Karpov vs Azmaiparashvili, USSR Championship, Moscow 1983: 1.e4 d6 2.d4 g6 3.Nf3 Nf6 4.Nc3 Bg7 5.Be2 O-O 6.O-O Bg4 7.Be3 Nc6 8.Qd2 e5 9.d5 Ne7 10.Rad1 b5 11.a3 a5 12.b4 axb4 13.axb4 Ra3 14.Bg5 Rxc3 15.Bxf6 Bxf3 16.Bxf3 Ra3 17.Bxg7 Kxg7 18.Ra1 Qa8 19.Rxa3 Qxa3 20.Be2 Qb2 21.Rd1 f5 22.exf5 Nxf5 23.c3 Qxd2 24.Rxd2 Ra8 25.Bxb5 Ra3 26.Rc2 Ne7 27.f4 exf4 28.Bc6 Nf5 29.Kf2 Ne3 30.Rc1 Kf6 31.g3 Ke5 32.Kf3 g5 33.gxf4+ gxf4 34.h4 Nxd5 35.Bxd5 Kxd5 36.Kxf4 Kc4 37.Re1 Rxc3 38.Re7 Kxb4 39.Rxh7 d5 40.Ke5 c6 41.Kd4 Rc4+ 0-1

Kasparov's Immortal; Rook and Knight Sacrifice.
Kasparov vs Veselin Topalov

Veselin Topalov

Veselin Aleksandrov Topalov is a Bulgarian chess grandmaster. He currently has the sixth highest rating in the world, and was the challenger facing world champion Viswanathan Anand in the World Chess Championship 2010, losing the match 6½–5½....

, Wijk aan Zee 1999: 1. e4 d6 2. d4 Nf6 3. Nc3 g6 4. Be3 Bg7 5. Qd2 c6 6. f3 b5 7. Nge2 Nbd7 8. Bh6 Bxh6 9. Qxh6 Bb7 10. a3 e5 11. O-O-O Qe7 12. Kb1 a6 13. Nc1 O-O-O 14. Nb3 exd4 15. Rxd4 c5 16. Rd1 Nb6 17. g3 Kb8 18. Na5 Ba8 19. Bh3 d5 20. Qf4+ Ka7 21. Rhe1 d4 22. Nd5 Nbxd5 23. exd5 Qd6 24. Rxd4 cxd4 25. Re7+ Kb6 26. Qxd4+ Kxa5 27. b4+ Ka4 28. Qc3 Qxd5 29. Ra7 Bb7 30. Rxb7 Qc4 31. Qxf6 Kxa3 32. Qxa6+ Kxb4 33. c3+ Kxc3 34. Qa1+ Kd2 35. Qb2+ Kd1 36. Bf1 Rd2 37. Rd7 Rxd7 38. Bxc4 bxc4 39. Qxh8 Rd3 40. Qa8 c3 41. Qa4+ Ke1 42. f4 f5 43. Kc1 Rd2 44. Qa7 1-0

Tal The Magician; Rook Sacrifice.
Mikhail Tal

Mikhail Tal

Mikhail Tal was a Soviet–Latvian chess player, a Grandmaster, and the eighth World Chess Champion.Widely regarded as a creative genius, and the best attacking player of all time, he played a daring, combinatorial style. His play was known above all for improvisation and unpredictability....

vs Tigran Petrosian

Tigran Petrosian

Tigran Vartanovich Petrosian was a Soviet-Armenian grandmaster, and World Chess Champion from 1963 to 1969. He was nicknamed "Iron Tigran" due to his playing style because of his almost impenetrable defence, which emphasised safety above all else...

, Moscow 1974: 1. Nf3 g6 2. e4 Bg7 3. d4 d6 4. Nc3 Nf6 5. Be2 O-O 6. O-O Nc6 7. d5 Nb8 8. Re1 e5 9. dxe6 Bxe6 10. Bf4 h6 11. Nd4 Bd7 12. Qd2 Kh7 13. e5 dxe5 14. Bxe5 Ne4 15. Nxe4 Bxe5 16. Nf3 Bg7 17. Rad1 Qc8 18. Bc4 Be8 19. Neg5+ hxg5 20. Nxg5+ Kg8 21. Qf4 Nd7 22. Rxd7 Bxd7 23. Bxf7+ 1-0

Candidates Jewel; Bishop Sacrifice.
Fischer vs Viktor Korchnoi, Curaçao

Curaçao

Curaçao is an island in the southern Caribbean Sea, off the Venezuelan coast. The Country of Curaçao , which includes the main island plus the small, uninhabited island of Klein Curaçao , is a constituent country of the Kingdom of the Netherlands...

1962: 1. e4 d6 2. d4 Nf6 3. Nc3 g6 4. f4 Bg7 5. Nf3 O-O 6. Be2 c5 7. dxc5 Qa5 8. O-O Qxc5+ 9. Kh1 Nc6 10. Nd2 a5 11. Nb3 Qb6 12. a4 Nb4 13. g4? Bxg4! 14. Bxg4 Nxg4 15. Qxg4 Nxc2 16. Nb5 Nxa1 17. Nxa1 Qc6 18. f5 Qc4 19. Qf3 Qxa4 20. Nc7 Qxa1 21. Nd5 Rae8 22. Bg5 Qxb2 23. Bxe7 Be5 24. Rf2 Qc1+ 25. Rf1 Qh6 26. h3 gxf5 27. Bxf8 Rxf8 28. Ne7+ Kh8 29. Nxf5 Qe6 30. Rg1 a4 31. Rg4 Qb3 32. Qf1 a3 33. Rg3 Qxg3 0-1

"Cheap's" Sacrifice.
Hikaru Nakamura

Hikaru Nakamura

Hikaru Nakamura is an American chess Grandmaster . He has been ranked among the top six players in the world by FIDE....

vs Ilya Smirin

Ilya Smirin

Ilya Yulievich Smirin is a Soviet-Israeli chess Grandmaster., his Elo rating was 2650, making him the 59th-highest rated player in the world...

, Foxwoods Open 2005: 1. e4 g6 2. d4 Bg7 3. Nc3 d6 4. f4 Nf6 5. Nf3 O-O 6. e5 Nfd7 7. h4 c5 8. h5 cxd4 9. hxg6 dxc3 10. gxf7+ Rxf7 11. Bc4 Nf8 12. Ng5 e6 13. Nxf7 cxb2 14. Bxb2 Qa5+ 15. Kf1 Kxf7 16. Qh5+ Kg8 17. Bd3 Qb4 18. Rb1 Bd7 19. c4 Qd2 20. Bxh7+ Nxh7 21. Qxh7+ Kf8 22. Rh4 1-0

ECO codes

Some of the systems employed by White against the Pirc Defence include the following:

4. Bc4 : ECO
Encyclopaedia of Chess Openings
The Encyclopaedia of Chess Openings is a classification system for the opening moves in a game of chess. It is presented as a five volume book collection describing chess openings...

code B07, Kholmov System (4.Bc4 Bg7 5.Qe2;
4. Be2 : ECO code B07 (sub-variants after 4..Be2 Bg7 include the Chinese Variation, 5.g4 and the Bayonet (Mariotti) Attack, 5.h4.)
4. Be3 : ECO code B07, 150 or "Caveman" Attack (4.Be3 c6 5.Qd2)
4. Bg5 : ECO code B07, Byrne Variation
4. g3 : ECO code B07, Sveshnikov System
4. Nf3 : ECO code B08, Classical (Two Knights) System (sub-variants after 4. ...Bg7 include 5.h3 and 5.Be2)
4. f4 : ECO code B09, Austrian Attack (sub-variants after 4.f4 Bg7 5.Nf3 0-0 include 6.e5, 6.Be2, 6.Bd3 and 6.Be3; also, after 4. ...Bg7 is 5.Bc4, the Ljubojevic Variation. Black also has the option to move into the Dragon Formation after 5.Nf3 with 5. ...c5.)