Modern Defense: Pterodactyl Eastern Benoni Variation
Modern Defense
Definition
The Modern Defense is a hyper-modern chess opening in which Black allows White to build an apparently imposing pawn center, only to undermine it later with timely pawn breaks and piece pressure. The most common move order begins 1.e4 g6, but the opening can arise against almost any first move by White. In ECO (Encyclopaedia of Chess Openings) codes it is filed under B06.
Typical Move Orders
- 1.e4 g6 2.d4 Bg7 3.Nc3 d6 – the “pure” Modern
- 1.d4 g6 2.e4 Bg7 3.Nc3 d6 – a transposition from the Pirc move order
- 1.c4 g6 2.Nc3 Bg7 3.d4 d6 – the English transposition
Strategic Ideas
- Hyper-modern Setup: Black places pawns on g6 and d6, fianchettos the king-side bishop to g7, and delays occupation of the center with pawns.
- Central Counter-thrusts: The pawn breaks …e5 and …c5 are crucial. The first hits the e4-pawn directly; the second attacks the d4-pawn from the flank.
- Flexible Pieces: Knights often head for d7 (supporting …e5) and c6. The queen is sometimes developed to a5 or b6, creating pressure on the long diagonal and queenside.
Historical Significance
Austrian grandmaster Karl Robatsch popularized the defense in the 1950s and 60s—hence the alternative name “Robatsch Defense.” The Modern fitted neatly into the hyper-modern school’s philosophy: control the center with pieces, not pawns. It has been employed, at least occasionally, by top players such as Bent Larsen, Judit Polgár, Hikaru Nakamura, and even Garry Kasparov (rapid & blitz).
Illustrative Game
(Shortened mini-game fragment showing how Black prepares …c5 and …e5. Full PGN omitted for brevity.)
Interesting Facts
- Because the same pawn structure can arise from several different openings (Pirc, King’s Indian, Benoni), Modern-Defense players often feel “at home” in a wide range of positions.
- GM Tiger Hillarp Persson once wrote that the Modern allows Black to “pass move one” and see how White commits his pieces before choosing a specific plan.
Standard Pterodactyl (Modern) Variation
Definition
The Pterodactyl is a flamboyant sub-variation of the Modern Defense distinguished by Black’s early …c5 and the dramatic queen sortie …Qa5—its silhouette on a diagonal flank attack supposedly resembles the outline of the prehistoric pterodactyl. “Standard Pterodactyl” refers to the line that arises after 1.e4 g6 2.d4 Bg7 3.Nc3 c5 4.dxc5 Qa5, aiming directly at the c5-pawn while eyeing the e1–a5 diagonal.
Main Line Moves
- 1.e4 g6
- 2.d4 Bg7
- 3.Nc3 c5
- 4.dxc5 Qa5 5.Bd2 Qxc5 6.Nf3
Key Concepts
- Early Material Imbalance: Black willingly concedes a pawn (…c5) to seize the initiative with …Qa5, recouping the pawn on c5 or c3 with active play.
- Diagonal Domination: The queen on a5 and bishop on g7 coordinate on the long a1–h8 line, often setting up tactics on c3 or d4.
- Unorthodox Development: Black delays kingside castling and sometimes parks the king on f8, retaining flexibility.
Historical & Practical Notes
The term “Pterodactyl” was introduced by British IM Mike Basman in the late 1970s, a decade famous for creative opening nomenclature (e.g., Orang-Utan, Hippopotamus). Though never a mainstream grand-master choice, it has scored well in club and correspondence play, where practical surprise value is high.
Example Miniature
This fragment shows Black regaining the pawn and opening lines for the g7-bishop.
Trivia
- Players fond of dinosaurs can adopt the sister lines “Western” and “Eastern” Pterodactyl, depending on where the queen makes its aerial strike—see below.
- Mike Basman’s booklets featured cartoon pterodactyls soaring over a chessboard, adding to the opening’s cult following.
Eastern Variation of the Pterodactyl
Definition
The Eastern Pterodactyl typically springs from Queen’s Pawn openings, especially the Benoni/King’s Indian move orders. The hallmark is again the sweeping queen sortie—but this time to a5 on the “east” side of the board (if we picture Black’s camp at the south, a5 lies to the east). A common sequence is:
- 1.d4 Nf6
- 2.c4 g6
- 3.Nc3 c5
- 4.dxc5 Qa5
This steals a tempo on the unprotected knight at c3 and prepares to recapture the pawn on c5.
Strategic Hallmarks
- Benoni Backbone: If White plays 5.Bd2 Qxc5 6.e4, the position resembles a Benoni Defense, but Black’s queen is unusually active.
- Rapid Queenside Play: Black often follows with …Na6–c5 and …d6, cementing a compact but dynamic structure.
- Surprise Factor: Because the line is rare at master level, theory is light, forcing opponents to think over the board.
Sample Continuation
Black has recovered the pawn and achieved a Benoni-type middlegame in which the queen keeps an active post.
Notable Encounters
- Basman – Webb, British Ch. 1980: The inventor ambushed his opponent, winning in 24 moves after a kingside piece storm.
- Hart – Hodgson, Lloyds Bank 1986: GM Julian Hodgson used the Eastern Pterodactyl to dispatch an IM in under 30 moves.
Fun Fact
Michael Basman humorously suggested renaming conventional Benoni lines as “Grounded Pterodactyls,” since the queen never gets to “fly” out to a5.
Benoni Variation (of the Pterodactyl/Modern)
Definition
The Benoni Variation is the most positionally sound branch of the Modern/Pterodactyl complex. Instead of grabbing the c-pawn immediately, Black allows a standard Benoni structure but reserves the option of playing …Qa5 or …Qb6 later. A typical path is:
- 1.d4 Nf6 2.c4 g6 3.Nc3 c5 4.d5 d6 5.e4 Bg7 6.Nf3 O-O
From here, Black may transpose into:
- Pterodactyl-Benoni: …Qa5 (mirroring the Eastern line but without an early pawn capture).
- Classical Modern-Benoni: …e6 followed by …exd5.
Strategic Themes
- Pawn Structure: The characteristic Benoni chain (d6-e6 vs d5-e4) yields a space advantage for White but dynamic piece play for Black.
- Piece Placement: The g7-bishop, knight on f6, and potential moves …Re8, …Na6-c7–b5 combine for queenside counterplay.
- Timing of …Qa5: Unlike the Standard Pterodactyl, Black often waits until White’s knight sits on c3 or bishop on e2, maximizing the tactical sting of the queen sortie.
Model Game
After 17…Qa5 Black introduces Pterodactyl motifs into a mainstream Benoni battle.
Historical Context
The Benoni Variation, while lacking a catchy dinosaur name, has been championed by several strong grandmasters—Tony Miles, Vugar Gashimov, and even Bobby Fischer (in analysis). Its hybrid nature lets Modern-Defense aficionados venture into the richer, more fully-developed Benoni theory when desired.
Interesting Tidbits
- Because the Benoni pawn structure can arise from a King’s Indian or Modern move order, database searches sometimes mis-classify these games; experienced players know to look up both ECO codes A60–A79 and B06.
- Computer engines rate many Benoni positions as suspect for Black at low depth, but human practice continues to demonstrate excellent practical chances—especially in rapid and blitz.