Chess Opening Theory/1. e4/1...c5/2. d4

Sicilian defence Sicilian defence B21 2. d4 White opens up the centre immediately. This is an uncommon but tactical sideline to avoid the conventional Open Sicilian. Today it is played with the idea of sacrificing a pawn for development and open lines. Black should play 2...cxd4, which was why they played 1...c5 in the first place. In the 19th century, 2. d4 was played with the idea of opening the centre and recapturing the pawn immediately: 2...cxd4 3. Qxd4!?. This is sometimes seen today, but it allows Black to develop with tempo on the queen (3...Nc6) for an even game. White has to move their queen again and suddenly their development advantage, and the whole reason for opening the centre in the first place, disappears. 3. Nf3, the Morphy gambit, sought to improve on 3. Qxd4 by preparing to retake with the knight. 3...Nc6 (say) 4. Nxd4 transposes back into the modern open Sicilian. However, Black has the addition resource of 3...e5!, securing the extra pawn and avoiding the transposition (4. Nxe5?? Qa5+!). Shuffling the move order gives us the modern main line: 2. Nf3 first, so that a. White can recapture on d4 with the knight not the queen, preserving tempo, and b. Black doesn't have time to play ...e5 and defend their d4 pawn. So is 2. d4 best consigned to the history books? No, because of the aggressive Smith-Morra gambit. Rather than retake the pawn, White can gambit it with 3. c3, the Smith-Morra gambit. If Black accepts, 3...dxc4 4. Nxc3, Black gets to keep the pawn but White is ahead in development with an open centre and lots of attacking opportunities. Anything other than 2...cxd4 for Black (2...d5?, 2...e6?!) is at best dubious. If Black wishes to avoid the Smith-Morra, then they're better off playing 2...cxd4 3. c3 d5 or 3...Nf6, transposing into an Alapin Sicilian. Theory table Smith-Morra gambit accepted 2. ... cxd4 3. c3 dxc3 4. Nxc3 Nc6 5. Nf3 d6 Smith-Morra gambit declined, Push var. 2. ... ... 3. ... d3 4. Bxd3 Nc6 5. Nf3 d6 Franco-Sicilian defence 2. ... e6 + References See also Smith-Morra Gambit