Blackmar-Diemer Gambit

The Blackmar-Diemer Gambit or BDG is a chess opening characterized by the moves

1. d4 d5

2. e4 dxe4

3. Nc3,

to be followed by f3 on White's fourth move.

This gambit is considered an aggressive opening, though its soundness continues to be the subject of much debate both on and off the chessboard. It arose as a development of the earlier Blackmar Gambit, named after Armand Edward Blackmar, a relatively little-known New Orleans player of the late 19th century who popularized its characteristic moves (1. d4 d5 2. e4 dxe4 3. f3) and was the first player to publish analysis on the opening in the chess literature.^[1]

The popularity of the original Blackmar Gambit, however, was short-lived, as it was basically unsound, allowing Black to equalize the position after White's immediate 3. f3 with 3... e5!; the best White reply being Be3. The evolved, modern form of gambit owes much to the German master Emil Josef Diemer (1908-1990), who popularized the interpolating move 3. Nc3, delaying the thematic f-pawn offer until the next move. The position resulting after 3. ... Nf6 4.f3 reflects the main line of the gambit accepted, although other Black responses on move three are possible. After many years of analysis, Diemer wrote a book on the opening in the late 1950s, titled Vom Ersten Zug An Auf Matt! (Toward Mate From The First Move!), with most of the published analysis devoted to the Halosar Trap (or Ryder Gambit), a double pawn sacrifice characterized by the moves 4...exf3 5. Qxf3.

It is easy for Black to decline the gambit on the second move with 2...e6 (leading to a French Defence) or 2...c6 (leading to a Caro-Kann Defence), although doing so does not eliminate White's ability to offer alternative gambits such as the Alapin-Diemer Gambit or the Diemer-Duhm Gambit.

As with most gambits, White aims to achieve rapid development and active posting of his pieces in order to rapidly build up an attack at the cost of the gambit pawn. It is one of the very few gambits available to White after 1.d4.^[2] Sidelines of the Blackmar-Diemer Gambit include the Ryder Gambit (5. Qxf3) and the Zilbermints Gambit (5. Nxf3 e6 6. Bg5 Be7 7. Bd3 Nc6 8. 0-0 Nxd4 9. Kh1), the latter being particularly unsound.

Dismissed by many masters, on the one hand, and embraced enthusiastically by many amateurs, on the other, it is most likely the case that, with accurate play, Black can defend his position and consolidate his extra pawn to good chances in the endgame. As a result, this opening is rarely seen in top-level play, but enjoys a certain popularity among club players.

Nevertheless, Chessgames[3] lists the Blackmar-Diemer as the most successful opening for White after 1. d4 d5.^[3]

Bogoljubov - Diemer, Baden-Baden 1952

I will add another version of the Halosar Trap, shortly, as always many variations, but I will show a slightly different version of the above trap.

Halosar Trap

This is just to give you a few ideas.

Nice Rod! I would like to add that even though certain people, especially on BDG-forums on the internet, claims that this gambit is sound, it is NEVER, ever played by the top players. Most likely because there are attractive ways to decline it, while accepting it also gives black an objective advantage. If one doesnt care too much about objective value or what the world elite plays (which is a very valid point of view) it is a lot of fun and creates very unbalanced positions, often with attacking chances.

1907

Coonitz-Solamon

(I may have spelled the names wrong but the year and game is correct)

another game

Quite a bit of computer analysis has been done with regard to the Blackmar-Diemer Gambit. Some of this computer analysis is posted on the Open Encyclopedia of Chess Openings and additional analysis is added each week. So far no one has proven a win for Black and the BDG appears to be a draw with best play. There are variations in which White must play precisely to hold on to the draw. However, there appear to be just as many or more variations in which Black is a single imprecise move away from a lost game.  

It is perhaps problematic to say that Black is objectively better if neither side can force a win in the BDG. Although we generally speak of advantages in chess, there still remains the question of whether the advantage has any real value. Any advantage which isn’t enough to turn a drawn game into a won game has no objective value. This statement assumes conditions of perfect play.  Of course there may be practical advantages to certain variations such as having the initiative or having extra material. It may be that a game containing such advantages is drawn with perfect play but the same variation may be practically more difficult for humans and/or computers to choose the right moves given the time constraint of play.  

But as the body of theory concerning a  variation grows and knowledge of this body of theory spreads throughout the chess community, these practical advantages become more or less valuable and sometimes they may nearly disappear completely (e.g. Scholar’s Mate?). If we were to view these value fluctuations in an equilibrium framework, we might say that practical advantages are short-run advantages and objective advantages are long-run advantages. Over time, the value of short-run advantages tend to converge upon the value of the long-run advantage due to a process of learning.  

So long as the BDG is never proven to be an objectively lost game for White and so long as there is no widespread knowledge of forceful drawing variations for Black, the BDG remains a playable opening in my opinion regardless of how fashionable the opening is at any level of play.

As mentioned earlier, there is also strong empirical evidence of the practical advantages for the player who handles the White pieces at the amateur level.  

This gambit is very fun to play and allows great creativity on both sides of the board. I like grabbing the pawn as black and saying "show me what you got, i'll play one of the most solid defences".

This. Word "refuted" started to go on my nerves very much. People here seems to believe that if you play opening that is "refuted" you will lose every single time. It only means that with perfect play on both sides, side that played "refuted" opening will be in slight or much worse position. And I must say again with PERFECT play. With my rating of 1800, and my opponents that are around 1800, we are million light years from perfect. I just blundered a rook after castle and won it in absolutely same way 3 moves after it. And we talk about not playing some opening because world top players don't play it?

Don't play KG (King's gambit), no ones play it today, don't play BDG (Blackmar diemer gambit), black will be in advantage. Don't even think about Danish gambit!!

I never had more fun on the chess board than when I played Danish gambit. Some of most beutiful games, and combinations I made while playing King's gambit.

I'm not planing to play 2500 player here, or some of world's top rated GM's in near future. And until that time comes, I will have my daily amount of fun playing

To refute is to admit that ze gambit is sound, it's a matter of ones own confidence, I love gambits, brings a more daring game, that one normally never a plays, yo!

I often follows it

I love the BDG, it's all about if your opponent accepts the bait, if so.. Hes in trouble. If not, however, you can go for a couple of more aggressive gambits, like the ADG or DDG, or black can go into the Karo-Kann D, or the French D. Still a huge advantage for white, hes down in material but his key is the castle on the queen side, both bishops are working together, once that happens. Prepare for the fireworks in both sides.

The blackmar diemar gambit have interesting games, not bad for bullet or blitz games.