Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6/3. Bb5/3...a6/4. Ba4/4...f5

Black offers the f-pawn in a bid for central control. This is not as popular as ...f5 on the third move, but delaying it until after playing ...a6 leads to some important differences which an unprepared player may not appreciate.

First among the differences is that d4!, which against the turn three Schliemann is a mistake, is the critical move.

5. d4! and Black's retort against d4 in the regular Schliemann, ...fxe4 Nxe5 Nxe5 dxe5 c6, no longer comes with tempo on the bishop. Therefore, Black's queen is unable to develop to the fifth rank with tempo, so 5...fxe4? 6. Nxe5 Nxe5 7. dxe5 c3? White has 8. Nc3±. The best continuation is 5...exd4 6. e5 b5 7. Bb3 and Black may play either 7...Na4 or 7...Bb7.

5. Nc3, the usual move against the regular Schliemann, also plays out differently here. The inclusion of ...a6 means Black can reply 5...b5 6. Bb3 b4 (kicking the knight) 7. Nd5 fxe4 (attacking the other knight), where White has to find 8. d4!, a shocking knight sacrifice, to stay ahead.

The deferred Schliemann's most famous recent outing was by Rameshbabu Praggnanandhaa in the 2024 Candidates tournament.^[1]

• Nunn's Chess Openings. 1999. John Nunn (Editor), Graham Burgess, John Emms, Joe Gallagher. ISBN 1-8574-4221-0.

• Kasparov, Garry, & Keene, Raymond 1989 Batsford chess openings 2. ISBN 0-8050-3409-9.

• Praggnanandhaa’s SECRET PREP | Deferred Schliemann Gambit vs Vidit Gujrathi | 2024 FIDE Candidates, FM William Graif. (Youtube)