# Accelerated London open a-file mistakes: game 1406

> Accelerated London open a-file mistakes in game 1406: I let a rook check on a1 slip through, then gave away a knight. Four verified boards from my loss.

- URL: https://thechesscoach.netlify.app/journey/opening-lesson-game-1406/
- Updated: 2026-11-02
- Author: Ignacio Soler

Accelerated London open a-file mistakes decided **game 1406**, a loss with White against **wali_M (1295)** on March 25, 2025. On move ten I opened the a-file myself. Two moves later I left my rook on a1 hanging to a rook check. My opponent didn't see it, but three moves after that I put a knight where Black's queen could take it, and I spent the rest of the game trying to get that piece back.

## The recorded game

I played it on my Chess.com account **nacsol3**, as White, in a ten-minute rapid game without increment. It is part of the sequence behind the [From 631 to 1385 journey](/journey/).

| Detail | Saved record |
|---|---|
| Game | 1406 |
| Opening | Queen's Pawn Opening, Accelerated London System (D00) |
| Opponent | wali_M, 1295 |
| Result | Loss (0-1), the record says "wali_M won - game abandoned" |
| Recorded rating | 1299 → 1291 |
| My accuracy | 69.1% (Black 71.8%) |
| My blunders / mistakes / inaccuracies | 6 / 3 / 3 |
| Accuracy by phase | Opening 73.5%, middlegame 66.8%, endgame 79.1% |
| My best winning chance in the game | 77.5% |
| Original score | [Chess.com game](https://www.chess.com/game/live/136648410914) |

It was not a good stretch. Games 1404 and 1405 were losses too, and game 1407 the same evening would be another one. My rating went from 1307 after game 1402 down to 1283 after game 1407. The [week 13 diary](/journey/week-2025-w13/) has the full list.

## How the opening went

The moves were 1.d4 d5 2.Bf4: the Accelerated London, with the bishop out before the knight. Black answered with a6, Nc6 and Bg4, the bishop pinning my knight on f3 to my queen. I played e3, Nbd2 and c3, and then 7.Qb3, the queen going after the b7 pawn. Black pushed it to b5. After 8.a4 Na5 my queen had to move again, to c2, and Black played c6.

Then came the decision that shaped the game: 10.axb5 axb5. Stockfish didn't mind it (its first choice was a knight move to e5, but the evaluation barely moved). What matters is what it did to the board. The a-file was now completely open, with my rook on a1 looking straight at Black's rook on a8. Black's rook was covered by the queen on d8. Mine was covered by nothing, and that would matter.

My 11.b4 was marked as an inaccuracy (from +0.96 to +0.23; the engine preferred the bishop to d3). It also left a hole on c4, and Black's knight jumped straight into it.

## Position 1: move 12, taking the knight

> **Game 1406, White to move on move 12**
> Position (FEN): `r2qkb1r/5ppp/2p1pn2/1p1p4/1PnP1Bb1/2P1PN2/2QN1PPP/R3KB1R w KQkq - 1 12`
> Played: Bxc4 — Bishop takes the knight on c4; Black can take back
> Better: Qc1 — Queen from c2 to c1, covering the rook on a1

Taking a knight that sits in the middle of my position felt natural. I had about eight and a half minutes on the clock and didn't think long. The analysis marks the capture as a blunder: **0.00 to -8.07**. The engine's preferred move is a quiet queen step back to c1, and its line continues with a bishop trade on f3, which the checker describes as just a trade.

What I didn't look at was the first rank. My bishop had been sitting on f1. Once it left, there was nothing between my two rooks, my king was still on e1, and no piece of mine guarded the rook on a1.

## Position 2: the reply Black didn't play

> **Game 1406, Black to move on move 12**
> Position (FEN): `r2qkb1r/5ppp/2p1pn2/1p1p4/1PBP1Bb1/2P1PN2/2QN1PPP/R3K2R b KQkq - 0 12`
> Played: dxc4 — Pawn takes the bishop on c4
> Better: Rxa1+ — Rook takes the rook on a1 with check

Here the checker is blunt: rook takes the rook in the corner, with check, and Black is "completely winning". Its line is 12...Rxa1+ 13.Ke2 Rxh1. My king steps up, and that opens the first rank so the same rook can also take my other rook in the far corner. Two rooks for nothing.

wali_M played 12...dxc4 instead, and the evaluation went back to **+0.62**, slightly better for me. I only found out about this whole exchange when I reviewed the game. During the game I had no idea that anything had happened on move 12.

The good news in the record is the next move. 13.O-O was Stockfish's choice too, and it is marked as a good moment in the lessons. After castling, my rook on f1 protected the rook on a1 along the first rank, so the open file stopped being a trap for me.

## Position 3: move 15, the knight that grabbed a pawn

After 13...Be7 14.Ne5 Qc8, the evaluation was **+1.86**, clearly better for me. My knight on e5 was strong, and Black's king was still in the centre.

> **Game 1406, White to move on move 15 (the turning point)**
> Position (FEN): `r1q1k2r/4bppp/2p1pn2/1p2N3/1PpP1Bb1/2P1P3/2QN1PPP/R4RK1 w kq - 4 15`
> Played: Nxc6 — Knight takes the pawn on c6 and attacks the bishop on e7, but it can now be captured
> Better: Qb2 — Queen from c2 to b2, keeping the pressure on the a-file

The checker's description of my move says it all in one sentence: the knight takes the pawn and attacks the bishop on e7, *but the knight can now be captured*. Black's queen on c8 took it. The evaluation went to **-4.93**, and this is the turning point the analysis records for the game.

The saved best move is the queen to b2, with a line where the rooks come off on a8 and my other rook takes the a-file. When I ran the checker again it put the immediate rook trade on a8 just above it, both "clearly better for White". Either way, the a-file was the place to play, and I went for a pawn instead.

## A piece down, and one more chance

For the next fifteen moves I was a piece down and the evaluation stayed between -5 and -6. Then, on move 30, Black gave it back: after my bishop took the knight on c7, Black's queen took back, and the analysis marks that as a blunder, from **-9.29 to -0.49**. The game was level again.

Five moves later Black blundered again with the pawn push 35...f4, and I was winning.

## Position 4: move 36, the pawn capture I didn't make

> **Game 1406, White to move on move 36**
> Position (FEN): `r5k1/8/2q1p2p/1p2P1p1/1PpP1p1P/2P2P2/3Q2K1/6R1 w - - 0 36`
> Played: Qf2 — Queen from d2 to f2
> Better: hxg5 — Pawn takes the pawn on g5, then attacks the undefended pawn on h6

Stockfish wanted my h-pawn to take on g5. The checker adds that the pawn then attacks Black's pawn on h6, which has no defender, and that the engine line follows up with my rook to the h-file. After that capture the evaluation was **+3.39**, "white is winning". I played 36.Qf2 and it went to **-0.65**. I had about three and a half minutes left.

From there the record is a string of swings. Black's 36...Kf7 handed me another edge (+1.37), my 37.hxg5 was marked as a mistake (0.00), and 38.Kh2, where the engine wanted my rook to h1, was a blunder (-5.70). Black blundered with 39...Qa6, I blundered back with 40.Kf1 and 41.Ke2. By move 50 I had about a minute and a half and a queen and two pawns against a queen and five pawns. The game ended there, abandoned.

## The lesson of game 1406

All three key moments in this game are about the same line of the board. I opened the a-file on move 10. On move 12 I took my bishop off the first rank without checking what the open file now allowed. On move 15 I had a good position built around that file, and I grabbed a pawn with my knight instead of using it.

So the review question I took from this game is simple: **when a file is open and the rooks face each other, before every move I check who protects my rook, and whether my move changes that.** For the general habit of checking what can be captured after my move, the [guide on how to stop hanging pieces](/guides/how-to-stop-hanging-pieces-in-chess/) has the routine I use. [Game 904](/journey/opening-lesson-game-904/) is another Accelerated London from earlier in the journey, with a very different mistake: a missed mate.

## What came next

The recorded ratings go 1299 before this game, 1291 after it and 1283 after the next one. They show a bad week; they don't prove anything about why. If you want to look at your own games this way, [Chess Coach in Claude or ChatGPT](/connect/) can review a finished game with these same boards and plain-word explanations, and the [journey hub](/journey/) has the rest of the series.

## FAQ

### What was the biggest mistake in game 1406?

My bishop took Black's knight on c4 on move 12. Stockfish rates it a blunder: the evaluation went from 0.00 to -8.07, because Black's rook could then take my rook on a1 with check.

### Did my opponent punish it?

No. wali_M recaptured with a pawn instead, and the evaluation came back to +0.62 for me.

### How did game 1406 end?

I lost. The record says wali_M won and that the game was abandoned after Black's 50th move, with the engine near -10 for White.

### What did the engine want on move 15?

Its saved choice was a queen move to b2, keeping pressure on the a-file. I took the pawn on c6 with my knight, and Black's queen simply took the knight.

## Related

- [From 631 to 1385: my chess journey in 2,117 games](https://thechesscoach.netlify.app/journey.md)
- [Week 63 (Mar 2025): 0–3 in the Pirc Geller System](https://thechesscoach.netlify.app/journey/week-2025-w13.md)
- [Accelerated London missed mate: my game 904](https://thechesscoach.netlify.app/journey/opening-lesson-game-904.md)
- [How to stop hanging pieces in chess: a safety routine](https://thechesscoach.netlify.app/guides/how-to-stop-hanging-pieces-in-chess.md)