USCF Home arrow Chess Life for Kids arrow 2008 arrow OPENING TRICKS AND TRAPS
By GM Susan Polgar   
September 29, 2008

GM Susan Polgar. Photo by Jeffrey Weiss
An important opening idea

I believe that for most scholastic players (at least until one reaches 1800 rating), very little specific opening knowledge is needed. On the other hand, being familiar with as many tactical and strategical ideas in the opening as possible can be very useful. This understanding can sometimes be useful in various openings as positions can transpose.

In this column, we shall look at a famous and beautiful idea that was invented by Mr. Legal a long time ago in the 18th century.

Legal’s Mate

1.e4 e5 2.Nf3 d6 3.Bc4 Bg4

Pinning the knight on f3 is often a good idea in similar positions, but as a rule of thumb, I prefer to wait with it until after White castles. The reason is that until then White by playing h2-h3, Bg4-h5 and g2-g4 does not weaken the king’s position as the king has not chosen yet to which side it will castle. Therefore, queenside castling would still be an option.


Now Black has to be careful not to fall into the famous trap.

4...Nc6 would not avoid the same trick either. 5.h3 Bh5? Of course, here Black could still avoid material loss by either trading on f3 or by retreating with the bishop on the c8-h3 diagonal. However, the whole idea of playing Bg4 was to create a pin over White’s knight on f3.

And here comes the famous “Legal Mate” idea: 6.Nxe5! Amazingly White can sacrifice the queen as after 6...Nxe5 at first it seems that actually White has fallen into a trap as after (If 6...Bxd1 a forced checkmate in two follows: 7.Bxf7+ Ke7 8.Nd5#) 7.Qxh5 Black can capture White’s bishop on c4 by 7...Nxc4. In this case, White has the final laugh after 8.Qb5+ forking Black’s king and knight! 8...c6 9.Qxc4 and it is White, who will be up a pawn at the end of all tactics.


Black’s best choice would have been 4...Nf6. The upcoming combination is possible due to fact that Black’s light squared bishop is on an unprotected square.

5.Nxe5!! Bxd1
This leads to an immediate loss. After 5...dxe5 White simply would capture Black’s Bishop with 6.Qxg4 winning a pawn. But that would have been Black’s best option anyway at this point.

6.Bxf7+ Ke7 7.Nd5#

A picturesque gorgeous checkmate!

As we shall see, the same theme can also arise from totally different openings.

Vucinic - Durovic
Yugoslavia, 1984

1.e4 Nf6 2.Nc3 d5 3.exd5 Nxd5

The game started out as an Alekhine defense, but now it resembles the Scandinavian defense more.

4.Bc4 Nb6

If 4...Nxc3 White can avoid doubled pawns (by b2xc3 or d2xc3) thanks to the intermediate move 5.Qf3 threatening Black’s f7 pawn and after 5...e6 6.Qxc3.

5.Bb3 e5?!

I would prefer the more solid 5...e6 lessening the power of White’s light- squared bishop.

6.d3 Nc6 7.Nf3 Bg4

Generally if this kind of pin cannot be maintained (as we shall see in this game) it makes no sense to create it in the first place.

8.h3 Bh5?

Again Black should have either traded on f3 or retreated back along the c8-h3 diagonal. Now we shall see a more complex version of Legal’s idea.


A brilliancy!! In this position, by White sacrificing his queen, he had to foresee more than ten moves ahead!


After 9...Nxe5 the answer would be 10.Qxh5 leaving Black a pawn down. It would still be better for Black than what happened in the game.

10.Bxf7+ Ke7 11.Bg5+

Unlike in the previous example, Nd5 does not make sense here.

This is an impressive way to continue the “king-chase” by sacrificing another knight. Capturing Black’s queen by 12.Bxd8? is not the right idea, as after 12...Nxe5 Black stays ahead, as both white bishops are under attack.

12...Kxe5 13.f4+ Kd4

So far so good, but White is running out of checks...and pieces.


A quiet move, being a queen down! Impressive! After 14.Bxd8 Bxc2 or 14.c3+ Kxd3 15.Rxd1+ Kxe4 Black would win easily.


In another game which reached this very same position, Black tried 14...Nb4 but White won quickly after 15.c3+ Ke3 and 16.0–0!, threatening checkmate with Rf1–e1. (But not 16.Rf1?? allowing Black to checkmate with 16...Nc2#) 16...Nxd3 17.Ng3. Another quiet move, threatening Rf1–f3 checkmate and Black resigned (Rozentalis - Mikenas, Vilnius, 1981).

If Black tries to save the queen by (for example) 14...Qd7 White can checkmate in two moves elegantly...can you see how?


The answer is: 15.c3+ Ke3 16.f5#.


Chasing Black’s king further into White’s territory. 15.fxg5 would open up a retreat square on e5, while 15.Nxg5 opens one on c5, giving the black king the opportunity to escape safely from the middle of the board.

15...Ke3 16.0-0

This is the best choice, threatening checkmate in three with Rf3+ Ke2, Rd2+ Ke1, and Rf1 checkmate!

16.fxg5 also was good enough to win: 16...Kf4 17.0-0+ Ke5 18.d4+ Kxe4 19.Rf3 followed by Rd1-e1.


Black could have delayed the end a bit longer by 16...Nd4 but not change the end result of the game.   

17.Rf3+ Ke2 18.Rd2+ 1-0

As I have often stated before, it is more important for young players to understand opening ideas rather than to memorize long variations. Also, don’t forget to improve your tactics and endgame. I offer free chess puzzles daily on my blog, www.susan , as well as my SPICE website, http://www.depts.ttu. edu/spice/ . Try to solve them daily and please feel free to let me know how you are doing by sending me an e-mail at Good luck!