Old Benoni

The Old Benoni, also called the Blackburne Defense after Joseph Henry Blackburne, who achieved early success with it, is the original form of the Benoni: Black meets 1. d4 with 1...c5 immediately. Because White has not yet played c2-c4, both sides keep options that the standard Benoni move order removes. Black can consider an early ...f5, or trade the dark-squared bishop with ...Be7-g5. White can develop with Nc3 while the c-pawn stays on c2, preparing a quick e2-e4.

The classical response is 2. d5, taking space and setting up a wedge, since 2. dxc5 e6 lets Black regain the pawn with ...Bxc5 without trouble. This capture is known as the Benoni Gambit Accepted. On Lichess the most frequent reply is 2. e4, which turns the game into a Sicilian and gives White the option of the Smith-Morra Gambit. 2. c4 is also common. Among the offbeat tries is 2. b4, the Zilbermints-Benoni Gambit. The engine rates the starting position as a slight edge for White and prefers 2. d5, with 2. e3 and 2. e4 as alternatives.

After 2. d5 Black has several setups. 2...e5 leads to Czech Benoni structures, coded separately as A44. The Schmid Variation, 2...d6 3. Nc3 g6, fianchettoes the king's bishop. One reason to delay ...Nf6 is to keep the long diagonal open: the knight can go to e7, and if White commits to Nc3 early, ...Bxc3 can double White's pawns. A fianchetto also lets Black wait for White to block the f-pawn with Nf3 and only then play ...e6 and ...exd5, reaching a Modern Benoni while sidestepping the Four Pawns Attack. The Mujannah Formation, 2...f5, uses the early ...f5 idea, fighting for e4 and building a kingside presence.

Top-level players have generally avoided the Old Benoni, but Alekhine defeated Bogoljubow with it during their 1934 match. It remains a fixture of online play. In Lichess games results are almost exactly even, with Black edging slightly ahead of White despite the engine's preference for White.