Adolf Anderssen vs Jean Dufresne

Alternative e5

The classical reply, meet the classical reply: e5 keeps the symmetry, e6 holds about as well at +0.3. Dufresne chooses the open game — and with it, everything that follows. Best was e6.

Inaccuracy Re1

10.Re1?! is a rare flicker of hesitation in an otherwise fearless game: the evaluation drifts from +0.4 to -0.2 for no visible reason. Anderssen wants the open file anyway — typical of the man who would spend three pieces seven moves later.

Mistake b5

11...b5 lunges for space at the wrong moment: from -0.5 the position swings to +0.8, and the initiative changes hands. The engine liked d5, striking the centre while Black's queenside remains loose. Best was d5.

Inaccuracy Bb7

A quiet improving move with a hidden cost: after Bb7 the evaluation edges from +0.7 to +1.5, because the queenside is left to look after itself. Dufresne develops; Anderssen sharpens.

Mistake Qf5

Qf5 walks into the crossfire: the advantage jumps from +1.3 to +3.0 in one tempo and White takes over, while d2 was the way to keep the balance. The black queen will now spend the rest of the game dodging — the chase begins. Best was d2.

Blunder Nf6+

Here the romantic era and the cold arithmetic part ways: Nf6+ throws a knight into the fire for the attack; the engine bills it on the spot, dropping from +3.5 to +0.4. Anderssen has seen something the depth-12 horizon has not — the king on e8 is running out of squares, and that is worth more than a knight. It gives check.

Brilliancy Rad1

Rad1!! is the move Lasker praised for its subtlety — while the engine is not impressed, reading -0.8 after it. But this is the hand that delivers mate five moves later, and that verdict is the only one that will survive the next ten plies. Anderssen has stopped counting material; the ledger will catch up in two more captures.

Excellent Rxe7+

Rxe7+ crashes into the knight with check, and every alternative is already lost — Be4 evaluates at -3.6. Anderssen gives a whole rook for a knight, and the number on the board still reads +2.3, because the mate is already in the air. It captures the knight on e7. It gives check. Best was Be4.

Brilliancy Qxd7+

Now the ledger breaks completely: Qxd7+ gives the whole queen, and the machine's answer is #3 — for White, not for Black. Dufresne must take — the king has no choice — and from there the checks alone finish the game. It captures the pawn on d7. It gives check. Black is up 6 points of material after the move.

Excellent Bf5+

Bf5+ forces the king to the back rank, and there is nothing else: Be2+ loses outright at -5.0. The check is only a way station — the engine sees #2 from here. It gives check. Black is up 15 points of material after the move. Best was Be2+.

Excellent Bd7+

Bd7+ is the last check before the door closes: the engine gives #1 here, while the only alternative Rd8+ walks straight into #-3. The light bishop has done its driving; the mate itself belongs to its quiet colleague on a3. It gives check. Black is up 15 points of material after the move. Best was Rd8+.

Checkmate Bxe7#

The finish: Bxe7# — the bishop that has stood on a3 since move eleven steps forward and ends the game by taking the knight. Anderssen spent a knight, a rook and a queen; the mating piece never left its square until the very last move. It captures the knight on e7. It is checkmate. Black is up 12 points of material after the move.