Janowski Variation

The Janowski Variation replaces the usual 3...Nf6 with a quiet pawn move that carries a concrete threat. After 3...a6, Black is ready to take on c4 and keep the extra pawn with ...b5, an idea shared with 3...c6. As with 3...Be7, the delay in developing the king's knight denies White the familiar Bg5 pin. White therefore has to choose a setup before Black's intentions are clear. The most direct reply is 4. cxd5, which removes the tension in the center and rules out the pawn grab. Engines also favor this move, rating White's position as slightly better. In online play, though, 4. Nf3 is the most frequent answer, ahead of 4. cxd5. With g5 offering little, 4. Bf4 is another option for the bishop.

The line was long a rarity. It gained interest in 2021, when World Champion Magnus Carlsen began to use it. In practice the results are close to even, with White only marginally ahead.