Greek Gift helped Marshall win in Ruy Lopez

The Marshall Attack in Ruy Lopez has established standard opening moves up to move 18...Qh5 (the Spassky Variation).  A video from youtube about this system is shown at the end of this article.

In this opening, when white moves 8.c3, it is like an invitation for black to enter the Marshall Attack line of the Ruy Lopez with the Marshall countergambit move of 8…d5. Black gives up a pawn for the initiative to attack.

I had a game in 5/0 Blitz sent for computer analysis yesterday playing black in this opening system. In this game, I deviated from the 13…Qh4 and decided to play chess my usual way – attack and in the process surprised my opponent with a sacrifice. In blitz, players can make a lot of mistakes especially when playing in unfamiliar lines and that element of surprise could translate into an overwhelming advantage. I decided to offer a sacrifice in a greek gift fashion with 13…Bxh2+.

Since I joined chess.com in February of this year, I have at least seven games that went into this opening system and won easily in all of them. From my games archive in live chess, they can be accessed through the following links:

It says that it has a 2200 strength which I assume that it means the computer software used can match up equally with players in around 2200 ratings. The game is shown here:

I have the following observations and comments on this analysis:

• On 13...Bxh2+, the computer said this is a book move. I guess no modern day chess master here will agree that 13...Bxh2+ is playable at their level.

• The book move is 13...Qh4 and I wonder which reference did the software use to refer to Bxh2+ as booked. 13...Bxh2+ is a losing move, a chess trap which is not advisable to use if you are playing against someone who knows that it is a trap.

• On 17.Be3, the chess.com analysis concurs. However, this is actually the move that made white fall into the trap. A computer analysis from my old laptop gave me the correct move and you will probably be able to figure it out even without the computer. Almost everyone fall into the trap because: first, it is a thematic move in the Marshall; second, it blocks black's threat of Rxe1; and third, the need to develop the bishop to its natural post makes it even more desirable.
  
  
• The computer did not see 18...Nh3+ which is another sacrifice. Only after the move that it gets its real numerical value. Innovative sacrifices like this are not being analyzed prior to the moves. They are only analyzed after the move by the software.

I sent another game of similar line that I played in chess.com for computer analysis after becoming a diamond member a few hours ago. It returned me the following image and pgn file:

The analysis still says that 13...Bxh2+ is a book move which is inaccurate because the book move for this particular opening is 13...Qh4. Wikipedia defines book move in its glossary of chess as an opening move found in the standard reference books on opening theory. A game is said to be "in book" when both players are playing moves found in the opening references. A game is said to be "out of book" when the players have reached the end of the variations analyzed in the opening books or if one of the players deviates with a novelty (or a blunder).

In the games explorer of chess.com, all of the 529 Marshall Attack games that reached 13. Re1 proceeded to 13...Qh4. We can therefore deduce from this sheer number of games that 13...Bxh2+ is not a standard move in the Marshall Attack. It is neither a book move as ECO lists this particular opening under Code C89 which has the book or standard moves shown below:

• C89 Ruy LopezMarshall Counter-attack 1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 Nf6 5.O-O Be7 6.Re1 b5 7.Bb3 O-O 8.c3 d5
• C89 Ruy LopezMarshall Counter-attack, 11...c61.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 Nf6 5.O-O Be7 6.Re1 b5 7.Bb3 O-O 8.c3 d5 9.exd5 Nxd5 10.Nxe5 Nxe5 11.Rxe5 c6
• C89 Ruy LopezMarshall Counter-attack, Kevitz Variation1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 Nf6 5.O-O Be7 6.Re1 b5 7.Bb3 O-O 8.c3 d5 9.exd5 Nxd5 10.Nxe5 Nxe5 11.Rxe5 c6 12.Bxd5 cxd5 13.d4 Bd6 14.Re3
• C89 Ruy LopezMarshall Counter-attack, Main line, 12.d2d41.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 Nf6 5.O-O Be7 6.Re1 b5 7.Bb3 O-O 8.c3 d5 9.exd5 Nxd5 10.Nxe5 Nxe5 11.Rxe5 c6 12.d4
• C89 Ruy LopezMarshall Counter-attack, Main line, 14...Qh31.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 Nf6 5.O-O Be7 6.Re1 b5 7.Bb3 O-O 8.c3 d5 9.exd5 Nxd5 10.Nxe5 Nxe5 11.Rxe5 c6 12.d4 Bd6 13.Re1 Qh4 14.g3 Qh3
• C89 Ruy LopezMarshall Counter-attack, Main line, Spassky Variation 1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 Nf6 5.O-O Be7 6.Re1 b5 7.Bb3 O-O 8.c3 d5 9.exd5 Nxd5 10.Nxe5 Nxe5 11.Rxe5 c6 12.d4 Bd6 13.Re1 Qh4 14.g3 Qh3 15.Be3 Bg4 16.Qd3 Rae8 17.Nd2 Re6 18.a4 Qh5
• C89 Ruy LopezMarshall Counter-attack, Herman Steiner Variation 1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 Nf6 5.O-O Be7 6.Re1 b5 7.Bb3 O-O 8.c3 d5 9.exd5 e4

Wikipedia defines chess trap as any move that tempts the opponent to make a losing move. This belongs to that category because it prepares the position where 17.Be3 becomes a losing move. As shown in all seven games I played on the Marshall Attack here at chess.com, black fell into the trap and only one game ended in a draw. See my blog on how Moniczka got a draw.

http://blog.chess.com/sollevy10/playing-the-marshall-with-moniczka-a-good-player

After I posted the blog on our games, I sent her a message to show her the link to what I had written and asked if she is a titled player. She replied that she has a first category in Poland with ELO rating greater than 2100. The point I am trying to arrive at is that the trap is also dangerous even against high-rated players. Even during our second game on the Marshall, she still fell into the trap. The game could have been another win but due to her creative tactic, which is typical of high-rated players, I was just lucky to have salvaged the game to a draw. Our second game however will demonstrate how black can convert its positional advantage into a material advantage in the event that white decides to give up the queen to avoid the checkmate.

You would however notice that Moniczka played 8.a4, an anti-Marshall move, However, after 8...b4, and 9.a5, the position allows black to move 9...d5 - the Marshall countergambit and still enter into the Marshall Attack line with the intention of trapping white in the same way as the main line move of 8.c3. Our games one and three are classified as C88 (anti-Marshall) but the trap has proven to be still usable.

Going back to the result of the computer analysis at 2500 rating level, the computer says that move 17.Be3 is a losing move and corrects the result of the analysis that was done at 2200-rating level.

This article demonstrates therefore the importance why we need to have a computer analysis of our games performed at the highest ELO rating of computer strength that is available to us. Handing out low-rated computer analysis is comparable to giving out inaccurate materials or information to the students of this game - the chess players, and could be disastrous or detrimental to our games come tournament or game time.