Semi-Slav Defense
also known as: ...e6 + ...c6 vs the Queen's Gambit
1. d4 d5 2. c4 c6 3. Nf3 Nf6 4. Nc3 e6
Named after
Named as the hybrid it is — half Slav (...c6), half QGD (...e6), and more ambitious than either.
Origin
The Meran Variation was analyzed by Akiba Rubinstein at the Meran tournament of 1924; Botvinnik's system (with ...dxc4 and ...b5 held back for war) was forged in the 1940s.
The story
The Semi-Slav plays both supporting moves and dares White to prove the light-squared bishop is really buried — because Black plans to take on c4 and blast it open with ...b5, ...Bb7 and ...c5 at the moment of maximum violence. Its two great tabiyas are named for a spa town (Meran 1924, where Rubinstein unveiled the plan) and a scientist (the Botvinnik System, a forcing labyrinth where both kings frequently die in the center and computer analysis has raged for eighty years). The Anti-Moscow Gambit revival of the 2000s made it, for a while, the sharpest mainstream opening on earth.
Why it matters
The fighting soul of the Queen's Gambit complex: Black accepts strategic risk to play for a win with the black pieces. The Botvinnik System in particular is theory's deepest jungle — a single prepared novelty at move twenty-five can decide a grandmaster game.
Notable games
- Botvinnik–Denker, USSR–USA radio match 1945
- Topalov–Kramnik, Elista WCh 2006 (Anti-Moscow wars)
- Aronian–Anand, Wijk aan Zee 2013 (a modern Meran immortal)