Zukertort Opening

The Zukertort Opening develops a knight, covers e5 and keeps every pawn at home, so White learns something about Black's intentions before choosing a structure. Because the knight already attacks e5, the symmetrical 1...e5 simply drops a pawn and carries the name Ross Gambit. After 1. e4 and 1. d4 it is the third most popular first move. Some writers call 1. Nf3 the Réti Opening, though that name more often refers specifically to 1. Nf3 d5 2. c4. Johannes Zukertort, who gave the opening his name, used it in his 1880 match with Samuel Rosenthal.

Much of the move's value lies in transposition. After 1...c5 White may enter an open Sicilian with 2. e4 or a Symmetrical English with 2. c4. Common routes lead to the Queen's Gambit Declined, as in 1. Nf3 d5 2. d4 Nf6 3. c4, or to the Catalan, as in 1. Nf3 Nf6 2. g3 d5 3. Bg2 e6 4. O-O Be7 5. c4. The knight move also filters out lines based on an early ...e5. A player who welcomes 1. c4 c5 but not the reversed Sicilian, or who wants the classical Nimzo-Larsen without meeting 1. b3 e5, can start with 1. Nf3.

On Lichess, 1...d5 is Black's most frequent answer, while 1...Nf6 leads at master level. Both prevent 2. e4. After 1...d5, White can choose between 2. d4 into a Queen's Pawn Game, 2. c4 for the Réti proper, 2. g3 for the King's Indian Attack, 2. b3 for the Nimzo-Larsen, and 2. d3, the Old Indian Attack, which prepares Nbd2 and e4. The rarer 2. Nc3 is the Reversed Mexican Defense, and 2. e4 is the Tennison Gambit. Against 1...Nf6, the pawn offer 2. e4 is the Lemberger Gambit. Black's other first moves, such as 1...e6, 1...c6, 1...d6 and 1...Nc6 (the Black Mustang Defense), are named as invitations to particular defenses that White may accept or decline.

White can also treat 1. Nf3 as an independent system. In the King's Indian Attack, White sets up with g3, Bg2, O-O, d3 and e4, leaving the queenside undefined, and keeps d4 available if Black commits to ...c5 and ...Nc6. In the Nimzo-Larsen setup, White plays b3, Bb2 and e3. In both, White hands Black the center early and aims to undermine it later, in hypermodern fashion. These flank lines need relatively little theory, and games often leave known territory quickly. The engine considers the position roughly balanced, and White scores somewhat better than Black in online play.