Grünfeld Defense: Three Knights Variation

About this variation

White develops with Nf3 before deciding on a plan, keeping options such as Bf4, Bg5 or Qb3.

The Three Knights Variation is 1. d4 Nf6 2. c4 g6 3. Nc3 d5 4. Nf3 Bg7. White develops a knight before deciding how to treat the center, and can then choose from several set-ups, including Bf4, Bg5, e3, Qb3, the exchange line with cxd5 and the modern 5. h4. The flexibility makes it a useful way to avoid Black's best-prepared lines.

The line with 5. Bf4 attacks c7 and puts pressure on Black's queenside, while 5. Bg5 targets the f6 knight and aims to weaken the d5 pawn. 5. e3 leads to a quieter position with a solid center, and 5. cxd5 Nxd5 6. e4 leads back to Exchange Variation structures with the knight on f3, a set-up that avoids some of Black's sharpest replies.

Black's plans include ...c5 to strike at the center, ...dxc4 to give up the center temporarily for piece activity, and ...O-O with ...c6 to build a solid structure. Black's bishop on g7 is the key piece, and Black often aims to open the long diagonal with ...c5 or ...e5.

White's plans depend on the chosen set-up. With Bf4 or Bg5, White often aims for queenside pressure and a lead in development. With e3, White builds a solid center and plays for a slow positional edge. In each case, White wants to restrict Black's bishop and keep the center stable.

The Three Knights Variation suits White players who want to choose the type of position after seeing Black's set-up. Black players need answers to each of White's main ideas, though the same principles of pressure on d4 and activity for the bishop on g7 apply throughout.

A practical tip is to learn the exchange line 5. cxd5 first, since it is the most common in master games, and then 5. Bg5 and 5. Qb3. Black players should know where they want their pieces in each case to avoid passive positions.

It is one of the main lines of the Grünfeld Defense.