Classical Game Deep Lines
More named sub-variations of the open games: Morphy Defence sub-lines, Italian regroupings, Scotch structures and the romantic gambit continuations that fill out the theory tree.
Classical Game Deep Lines is one of the most compelling entries in the Encyclopaedia of Chess Openings — and a line that repays every hour you sink into it.
After 3…a6 the position resolves into a tense centre: the central pawns still face each other, and the timing and manner of the coming exchange shapes the whole middlegame.
The moves
After 3... a6 — Classical Game Deep Lines main line
Position breakdown
A factual read of the position after the main line — the files, the centre, the pawn structure and king safety that decide how the middlegame is played. These are computed from the actual board, not generic advice.
Files
Centre control
Tense centre
The d4/d5/e4/e5 squares — who occupies the centre decides how open the game becomes.
Pawn skeleton
Pawns only — the structure that explains every open file and majority at a glance.
Material level
Queenside pawns 3–3
Kingside pawns 3–3
Development
Knight & light-squared bishop active
Knight active
King safety
White king e1
Uncastled — take care
Black king e8
Uncastled — take care
Computed from the final position of the main line above — 6 plies, white to move.
Strategic ideas
Ideas for White
Learn the main tabiyas: most of these lines converge on a handful of key structures.
Ideas for Black
Know your one defence deeply rather than ten shallowly — open games punish vague preparation.
Main variations (58)
Ruy, Morphy 4.Bxc6
C68The immediate trade: the structure decision arrives at once.
Ruy, Morphy 4.Ba4 d6
C71The Modern Steinitz move order: solid and flexible.
Ruy, Morphy 4.Ba4 Nf6 5.Qe2
C77The Qe2 setup: defending e4 while dodging main-line theory.
Ruy, Siesta 6...Bd7
C74The ...Bd7 setup: solid development in the Steinitz complex.
Ruy, Berlin 4.d3
C65The d3 setup: the Bishop's-Opening-style transposition.
Ruy, Berlin 4.O-O d6
C66The closed Berlin: solid ...d6 development a tempo up.
Ruy, Exchange 5.O-O
C68The castling-first Exchange: flexible and solid.
Ruy, Exchange 5.d4
C68The immediate central strike: opening the position at once.
Ruy, Closed 6.Qe2
C86The Worrall Attack: Qe2 guards e4 and keeps the rook free.
Ruy, Closed 6.d3
C84The d3 setup: the flexible modern treatment of the Closed Ruy.
Ruy, Closed 6.d4
C84The early d4 strike: opening the centre immediately.
Ruy, Berlin 4.Qe2 Setup
C65The ...b5 kick: asking the bishop to decide immediately.
Italian, 3...Nf6 Setup
C55The Two Knights move order: counterattacking e4 at once.
Italian, 4.d4 exd4
C50The central strike: the gambit lines begin.
Italian, 4.O-O Setup
C50The castling-first setup: solid Italian development.
Italian, 4.b4 Evans
C51The Evans strike: the romantic pawn sacrifice at once.
Italian, Hungarian 4.c3 Setup
C50The c3 build-up: solid development against the Hungarian.
Italian, 4.d3 Bc5 5.Nbd2
C55The d3/Nbd2 setup: the solid modern treatment.
Scotch, 4.Nxd4 Qh4 5.Nc3
C45The Nc3 development: developing while dodging the queen tricks.
Scotch, 4...Nf6 5.Nb3
C45The Nb3 retreat: the modern solid treatment of the Schmidt complex.
Scotch, Göring 5.Bc4
C44The Bc4 development: attacking f7 in the Göring gambit.
King's Gambit, 2...Bc5 Decline
C30The classical decline: developing with tempo.
King's Gambit, 2...Qh4+ Strike
C33The queen check: the classical KGA counterattack.
King's Gambit, 3.Nf3 d6
C34The ...d6 support: solid consolidation in the KGA.
King's Gambit, Bishop's 4.Nf33.Bc4 Qh4+ 4.Kf1 d5 Setup
C33The ...d5 strike: the central counterattack against the Bishop's Gambit.
Vienna, 2...Nc6 3.f4
C25The f4 strike against ...Nc6: the romantic gambit begins.
Vienna, 3.Bc4 Nxe4 4.Qh5
C28The Qh5 probe: the famous Vienna attacking line.
Four Knights, Glek 4.g3 Bc5
C46The ...Bc5 setup: the Italian structure inside the Glek.
Petrov, 3.d4 exd4
C43The exchange release: the Steinitz Attack's main continuation.
Ponziani, 3...d5 4.exd5
C44The exchange: the clean central resolution.
Danish, 4.Bc4 Main
C21The bishop development: the Danish's main attacking setup.
Elephant, 3.exd5 e4
C40The ...e4 push: the Elephant's radical pawn structure.
Latvian, 3.Nxe5 Qf6 4.d4 d6 Setup
C40The ...d6 support: the classical Latvian structure.
Blackmar-Diemer, 4.f3 dxf3
D00The f3 strike: the BDG's second pawn sacrifice.
Centre Game, 4.Qe3 Nf6
C22The Qe3 retreat: keeping the extra tempo safely.
Giuoco Piano, 7.Nc3 Setup
C53The Nc3 block: the main Giuoco Piano continuation.
Two Knights, 5...Na5 6.Bb5+
C58The check: the classical main line's forcing start.
Two Knights, 4.d4 exd4 5.e5
C56The e5 wedge: chasing the knight and gaining space.
Evans, 5...Ba5 Main
C51The ...Ba5 retreat: the main Evans battleground.
Evans, 5...Be7 Decline
C51The ...Bb6 decline: keeping the bishop active.
Ruy, Berlin Wall 9.Nc3
C67The Nc3 development: the Berlin endgame's main line.
Ruy, Berlin Open 5.Re1
C65The Re1 pressure: the Open Berlin's main line.
Ruy, Open 8.dxe5 Be6
C80The ...Be6 setup: the Open Ruy's main consolidation.
Scotch, 4...d6 Setup
C45The ...d6 support: keeping the structure solid in the Scotch.
Petrov, 3.Nxe5 d6 4.Nf3 Nxe4 5.Qe2
C42The Qe2 probe: pressuring the e4 knight immediately.
Philidor, 3.d4 exd4 4.Qxd4
C41The queen recapture: fast development in the Philidor.
Bishop's, 2...Nf6 3.d3
C23The d3 setup: solid development in the Bishop's Opening.
Bishop's, 2...c6 Setup
C23The ...c6 support: preparing ...d5 against the bishop.
Ruy, Cozio 4.Ba43...Nge7 Setup
C60The Cozio knight setup: the safest Ruy defence.
Ruy, Bird 4.Nxd4 exd4
C61The exchange: the Bird's structural solution.
French, Winawer 7.Qg4 Qc7 8.Qxg7
C19The g7 grab: White takes the poisoned pawn of the French.
French, Advance 6.Be3 Qb6
C02The Be3 block: covering b2 and preparing the defensive development.
French, Tarrasch 3...Nf6 5.f4
C03The f4 support: the Tarrasch's space-grabbing plan.
French, Classical 7.Be3 Qb6 8.Ne2
C11The Be3 development: the classical French tabiya.
Ruy, Exchange 5...Bd6
C68The ...Bd6 setup: solid development with the bishop aimed at h2.
Ruy, Closed 9...Na5 Setup
C96The ...Na5 strike: the Chigorin's queenside pressure begins.
Italian, Giuoco Fortissimo
C53The Fortissimo: maximum open-line chaos in the main Italian.
Two Knights, Fritz Setup
C57The d4 support: the solid alternative to the Fried Liver.
Plans & pawn structures
- 1The central tension is the key decision: releasing it too early hands the opponent a free tempo and a target, so keep it until a capture wins a file, a diagonal or a clear structural edge.
- 2Develop with a purpose: connect the pieces to a concrete plan (a break, a target square, an outpost) instead of making automatic moves.
- 3Trade correctly: before every exchange ask which piece benefits from the resulting square colours and pawn structure.
Typical middlegame structures
The main line leads to a tense centre: the central pawns still face each other, and the timing and manner of the coming exchange shapes the whole middlegame. No files have opened yet, so this is a manoeuvring struggle: improve your pieces and prepare the pawn break that will open the position on your terms.
Traps & tactical motifs
Every sharp opening has its traps — study the forcing lines around the centre and the f7/f2 squares before playing this in rated games.
Watch the typical motifs: pins against the pinned piece, knight forks after the natural captures, and queen sorties to a2/g2-style squares.
How to Play Against the Classical Game Deep Lines
- As White, resolve the central tension on your terms: force the exchange that gives you the better structure rather than letting the opponent choose the moment.
Study plan & who it's for
Solidly intermediate. The main lines require real study, but the payoff is positions you can play for a lifetime. Best investment for Black players around 1400–2000.
Play through the main line above until the piece setup feels natural.
Learn the two or three critical pawn breaks for both sides.
Drill one variation at a time — always connecting moves to plans.