Reti: 1...c5, Nimzowitsch-Larsen

Réti: 1…c5

Definition

The line “Réti: 1…c5” arises after the opening move 1. Nf3 c5. It is catalogued in the ECO as A11 and represents Black’s immediate bid for central and queenside space against the hyper-modern Réti Opening. By playing …c7-c5 at once, Black challenges the d4-square in Sicilian style while retaining flexibility in the king-pawn structure.

Typical Move Orders

• 1. Nf3 c5 2. c4 – White turns the game into an English Opening with colors reversed.
• 1. Nf3 c5 2. e4 – A direct transposition to a Sicilian Defence where White has lost a tempo yet kept flexibility; popular in faster time controls.
• 1. Nf3 c5 2. g3 Nc6 3. Bg2 – Retains independent Réti character, placing the bishop on the long diagonal before committing the c-pawn.

Strategic Themes

• Hyper-modern central control – White often attacks the dark squares (d5, e4) from afar with pieces and pawn thrusts like c2-c4 or d2-d4 later.
• Sicilian in reverse – After 2.e4, White must prove that the extra tempo compensates for Black’s solid Sicilian structure.
• Flank vs. center – Black’s …c5 stakes ground on the queenside, but leaves d5 and e5 slightly loosened; White can aim for breaks with d2-d4 or b2-b4.

Historical Context

Richard Réti popularized 1.Nf3 in the 1920s, emphasizing piece pressure on the center rather than immediate occupation. The direct reply 1…c5 gained traction later, chiefly among players seeking an early asymmetry without committing the d-pawn. Grandmasters such as Bent Larsen, Ulf Andersson, and more recently Magnus Carlsen have used the line as a surprise weapon.

Illustrative Mini-Game

A crisp illustration of the reversed Sicilian spirit:

Interesting Facts

• ECO splits the Réti into A04-A09 (1…Nf6) and A10-A13 (1…c5/…d5), demonstrating how Black’s very first move determines the entire classification.
• Because White can still transpose to a standard Sicilian with the extra tempo, some theoreticians nicknamed the line the “Sonic Sicilian.”
• In rapid chess, 2.e4 after 1…c5 has scored remarkably well for White (>60 % in large databases) thanks to surprise value.

Nimzowitsch-Larsen (1. b3)

Definition

The Nimzowitsch-Larsen Attack, most simply identified by the move 1. b3, is a flank opening where White fianchettoes the queen’s bishop to exert long-range pressure on the central dark squares (e5, d4) before committing central pawns. It is classified under ECO codes A01–A02.

Key Ideas

• Early fianchetto – 2.Bb2 aims at g7, f6, e5, and can become combustible if Black plays …e5 too soon.
• Flexible center – White often delays d2-d4/e2-e4, choosing the right moment based on Black’s setup.
• Quick castling – With Nf3, g3, Bg2, and O-O, White reaches safety rapidly and keeps options for pawn storms on either wing.

Typical Structures

1. Larsen–Petrosian system: 1.b3 e5 2.Bb2 Nc6 3.e3 d5 4.Bb5 – White pins the knight and looks for c2-c4 breaks.
2. Modern double-fianchetto: 1.b3 d5 2.Bb2 Nf6 3.g3 g6 4.Bg2 Bg7 – Both sides adopt hyper-modern formations.
3. Reverse Nimzo-Indian: 1.b3 Nf6 2.Bb2 e6 3.Nf3 b6 4.e3 Bb7 – The resulting middlegame mirrors a Nimzo-Indian with colors switched.

Historical Significance

Although named after Aron Nimzowitsch, it was Danish grandmaster Bent Larsen who transformed 1.b3 into a lethal weapon in the 1960s–70s. His victories against world-class opponents (e.g., Larsen–Spassky, Belgrade 1970) showed that a flank opening could generate brute attacking chances when handled dynamically.

Notable Game Snapshot

Larsen–Spassky, USSR vs. Rest of the World, Belgrade 1970:
– Larsen sacrifices structure for an initiative that eventually topples the former World Champion.

Practical Usage

• Surprise value – Rare at elite level today, 1.b3 can knock opponents out of mainstream opening theory by move one.
• Versatility – The opening can transpose into English, Queen’s Indian, or even Dutch-type positions, suiting players who relish unexplored paths.
• Engine approval – Modern engines rate 1.b3 only marginally below 1.e4/1.d4, making it a sound yet creative alternative.

Curiosities

• GMs Hikaru Nakamura and Richard Rapport have used 1.b3 in blitz to devastating effect; Rapport once beat Fabiano Caruana in under 20 moves.
• Magnus Carlsen tried 1.b3 against Wesley So in the 2015 Asian Millionaire Open, later joking, “I felt like Larsen with better computers.”
• The line once appeared in correspondence chess labeled “Baby Orangutan,” a playful nod to the more famous 1.b4 Orangutan Opening.