Openings · A01

Larsen's Opening

1.b3 — the bishop goes to b2 on move two and looks down the long diagonal for the rest of the game.

1.b3played as White

The idea

Fianchetto first, decide about the centre later. The bishop on b2 hits e5 and g7, and White follows with e3, Nf3 and either f4 or c4 depending on what Black has built.

It is a genuine opening with a genuine drawback: it does nothing about the middle of the board, and 1…e5 followed by …Nc6 and …d5 gives Black a big centre for free. The bishop has to be worth the pawns it is not putting there.

Practise the line

You play White; the other side answers on its own. Nothing here is saved or graded.

Your move 1 of 10/1

1.b3

Your move. Drag a piece, or tap it and then its square.

Common mistakes

Three that come up again and again below master level. Each is ordinary opening theory — a named trap, or the error every coach corrects — not a statistic, and not drawn from anybody's games.

Hitting the centre before castling

1.b3 e5 2.Bb2 Nc6 3.e3 d5 4.Bb5 Bd6 5.f4 Qh4+

The mistake: Playing f4 to challenge the big black centre with the king still on e1.
Why it costs: The f-pawn's departure opens the e1–h4 diagonal, and …Qh4+ arrives with tempo before White has castled. Black gets to develop with checks, which is the one thing a slow opening cannot afford.
Instead: Nf3 first, and f4 later if at all. Against a strong centre the useful moves are the ones that hit it without loosening the king.

Putting a pawn on the bishop's diagonal

1.b3 d5 2.Bb2 Nf6 3.e3 e6 4.Nf3 Be7 5.d4 O-O 6.Bd3 c5 7.c3

The mistake: Playing d4 and c3 in front of the bishop that the whole opening was built round.
Why it costs: d4 and c3 are both on the a1–h8 diagonal. The bishop on b2 was the reason for 1.b3, and it now sees the back of two of its own pawns while Black has an ordinary, comfortable Queen's-Gambit-style position.
Instead: Keep the d-pawn on d3 and fight for e5 with f4 or with pieces. The pawn goes to d4 when it wins that square rather than when it blocks the bishop.

Opening lines beside your own king

1.b3 e5 2.Bb2 Nc6 3.c4 Nf6 4.Nf3 e4 5.Nd4 Bc5 6.Nxc6 dxc6 7.e3 Bf5 8.Qc2 Qe7 9.Be2 O-O-O 10.f4

The mistake: Playing f4 with the king uncastled and Black's rooks already connected — Larsen against Spassky, 1970.
Why it costs: Spassky answered 10…Ng4, met 11.g3 with 11…h5, and the h-pawn arrived with the file opening in front of it. The game finished 14…Rh1 and mate on move seventeen, and White never made a move that looked like a blunder.
Instead: Castle, or at least play h3 and Nc3 before touching the f-pawn. In this opening the king lives in the middle longer than usual, so lines have to stay shut longer than usual too.

Try it on one of your own

The board above is for the line itself; this is for a game you played. Paste a game in this opening, or pull one from chess.com, and every move is graded against what the engine would have played. Open the board, read how the grading works, or go back to the other openings.