Cambridge Springs Defence (...c6, ...Nbd7, ...Qa5) is variation 6 of 6 in the Queen's Gambit Declined course, a intermediate opening course for Black (ECO D52). It runs 25 moves and begins 1. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Bg5 Nbd7 …. Black uses the pin on the c3 knight: ...Qa5 and ...Bb4 hit c3 and the g5 bishop on the fifth rank. White usually plays Nd2 and Qc2, and Black breaks with ...e5 for active play. In the lesson every move is explained on a board and then drilled; it is free.
Move by move
1. d4 – White takes the centre.
1... d5 – Black stakes a claim.
2. c4 – The Queen's Gambit.
2... e6 – Supports d5.
3. Nc3 – Puts more pressure on d5.
3... Nf6 – Develops and defends d5.
4. Bg5 – Pins the f6 knight.
4... Nbd7 – Defends f6 again and sets the Elephant trap: 5.cxd5 exd5 6.Nxd5?? loses a piece.
5. e3 – Solid support for d4.
5... c6 – Prepares ...Qa5 along the a5-d8 diagonal and supports d5.
6. Nf3 – Develops and covers e5.
6... Qa5 – The Cambridge Springs: the queen pins the c3 knight and eyes the g5 bishop along the fifth rank once d5 is gone.
7. Nd2 – The main answer: the knight defends against ...Ne4, protects c4 and frees the f-pawn.
7... Bb4 – Adds a second attacker to the pinned c3 knight.
8. Qc2 – Defends c3 again and covers e4.
8... O-O – Black castles before opening the centre.
The lesson goes on for 9 more moves, each with its explanation.
chessGM