Lucena position - AbsoluteAstronomy.com

The Lucena position is one of the most famous and important positions in chess

Chess

Chess is a two-player board game played on a chessboard, a square-checkered board with 64 squares arranged in an eight-by-eight grid. It is one of the world's most popular games, played by millions of people worldwide at home, in clubs, online, by correspondence, and in tournaments.Each player...

endgame theory, where one side has a rook

Rook (chess)

A rook is a piece in the strategy board game of chess. Formerly the piece was called the castle, tower, marquess, rector, and comes...

and a pawn

Pawn (chess)

The pawn is the most numerous and weakest piece in the game of chess, historically representing infantry, or more particularly armed peasants or pikemen. Each player begins the game with eight pawns, one on each square of the rank immediately in front of the other pieces...

and the defender has a rook. It is fundamental in the rook and pawn versus rook endgame. If the side with the pawn can reach this type of position, he can forcibly win the game. Most rook and pawn versus rook endgames reach either the Lucena Position or the Philidor Position

Philidor position

The Philidor position usually refers to an important chess endgame which illustrates a drawing technique when the defender has a king and rook versus a king, rook, and a pawn. It is also known as the third rank defense, because of the importance of the rook on the third rank cutting off the...

if played accurately . The side with the pawn will try to reach the Lucena Position to win; the other side will try to reach the Philidor Postion to draw

Draw (chess)

In chess, a draw is when a game ends in a tie. It is one of the possible outcomes of a game, along with a win for White and a win for Black . Usually, in tournaments a draw is worth a half point to each player, while a win is worth one point to the victor and none to the loser.For the most part,...

.

The position is incorrectly named after the Spaniard Luis Ramirez de Lucena. The name "Lucena" is pronounced "Loo THAY na" in Castilian Spanish

Spanish language

Spanish , also known as Castilian , is a Romance language in the Ibero-Romance group that evolved from several languages and dialects in central-northern Iberia around the 9th century and gradually spread with the expansion of the Kingdom of Castile into central and southern Iberia during the...

Introduction

The so-called Lucena position is named after the Spaniard Luis Ramírez de Lucena, although is something of a misnomer, because the position does not in fact appear in his book on chess, Repetición de Amores e Arte de Axedrez (1497). It does appear, however, in Alessandro Salvio

Alessandro Salvio

Alessandro Salvio was an Italian chess player who is considered to be the unofficial world champion around the year 1600. He started an Italian chess academy in Naples, Italy, and wrote a book called Trattato dell'Inventione et Arte Liberale del Gioco Degli Scacchi, which was published in Naples...

's Il Puttino (1634), a romance on the career of the chess player Leonard da Cutri, and it is in that form that it is given here . Salvio attributes it to Scipione Genovino .

The position is shown above and below (the position can be moved as a whole or mirrored so that the pawn is on any of the files b through g). White's aim is to either promote

Promotion (chess)

Promotion is a chess rule describing the transformation of a pawn that reaches its eighth rank into the player's choice of a queen, knight, rook, or bishop of the same color . The new piece replaces the pawn on the same square and is part of the move. Promotion is not limited to pieces that have...

his pawn

Pawn (chess)

or else compel Black to give up his rook for it – either result will leave White with an overwhelming material advantage and a straightforward win. White has managed to advance his pawn to the seventh rank, but it is prevented from queening because his own king is in the way. White would like to move his king and then promote his pawn, but is prevented from moving to the a-file by the black rook, and prevented from moving to the c-file by the black king.

The essential characteristics of the position are:

the pawn is any pawn except a rook pawn
the pawn has advanced to the seventh rank
the attacking king (the one with the pawn) is on the queening square
Promotion (chess)
Promotion is a chess rule describing the transformation of a pawn that reaches its eighth rank into the player's choice of a queen, knight, rook, or bishop of the same color . The new piece replaces the pawn on the same square and is part of the move. Promotion is not limited to pieces that have...

of its pawn
the attacking rook cuts off the opposing king from the pawn by at least one file
the defending rook is on the file on the other side of the pawn

An obvious approach by White (in the position above) such as

1. Rd1+ Ke7

2. Kc7

gets nowhere. Black can simply harass the white king with checks, and White makes no progress:

2... Rc2+

3. Kb6 Rb2+

4. Ka7 Ra2+

5. Kb8

The winning method: building a bridge

In the Lucena position, the side with the pawn has a winning method that works for any pawn except a rook pawn (i.e. on the a- or h-file). In some circumstances, it also works for a rook pawn.

In this position, White can win with

1. Rd1+ Ke7

2. Rd4!

Now, if Black plays a waiting move, such as

2... Ra1

hoping to harass the white king with checks again as in the above variation, White continues

3. Kc7 Rc1+

4. Kb6 Rb1+

5. Kc6 Rc1+

(Or 5.Ka6 Ra1+.)

6. Kb5 Rb1+

7. Rb4!

The black rook can no longer check the white king and Black cannot prevent the pawn from queening . White's shielding his king and pawn with the rook in this way was described as "building a bridge" by Aron Nimzowitsch

Aron Nimzowitsch

Aron Nimzowitsch was a Russian-born Danish unofficial chess grandmaster and a very influential chess writer...

.

It is important that the white rook go initially to the fourth rank if Black uses his most active defense: repeatedly checking the white king. If Black abandons this defense, the white rook can build a bridge on the fifth rank. In the line above, after

5. Kc6

if Black moves

5... Ke6

there is a trap for White: if 6.Rd5?? (to build a bridge on the fifth rank) then 6...Rxb7! draws

Draw (chess)

. However, if

6. Rd6+ Ke7

7. Rd5!

and White can build a bridge on the fifth rank by getting the rook to b5, the king to b6, and then the pawn can promote (position reflected):

7... Rc1+

8. Kb6 Rb1+

9. Rb5

and White wins.

Black to move

If Black is to move in the diagrammed position, he can prevent the white rook from going to the fourth rank, but then White still wins:

1... Ra4

2. Rd1+ Ke7

3. Kc7 Rc4+

4. Kb6 Rb4+

5. Ka6 Rb2

(The black rook is not far enough away to keep checking: if 5...Ra4+ then 6.Kb5 wins.) Now White wins by blocking the checks with

6. Rd5

followed by

7. Rb5 (position reflected).

Bridge on the fifth rank

A bridge can also be built on the fifth rank (but it is better to build one on the fourth rank). The main line goes:

1. Rf5

(Instead of 1.Rf4!)

1... Rc1

2. Ke7

Threatening to promote the pawn, Black can just delay it with checks.

2... Re1+

3. Kd6 Rd1+

4. Rd5

and the pawn will promote. Or

1... Kg6

2. Ke7?!

Better is 2.Rf8 Kg7 3.Rf4!, back to a bridge on the fourth rank.

2... Kxf5!

3. d8=Q

and White has a winning (but difficult) queen

Queen (chess)

The queen is the most powerful piece in the game of chess, able to move any number of squares vertically, horizontally, or diagonally. Each player starts the game with one queen, placed in the middle of the first rank next to the king. With the chessboard oriented correctly, the white queen starts...

versus rook endgame (see pawnless chess endgame) .

Alternate plan for the defense

Alternative approaches are no better for Black. After 1.Rd1+ Ke7 2.Rd4 above, after

2... Rb2

for example, White can still carry out his plan as above, or he can win with the simple

3. Ra4 Kd7

4. Ka8 (or 4.Ka7) Kc7

5. Rc4+

which chases the black king away and allows the pawn to promote. (Or, 5.b8=Q+ Rxb8 6.Rc4+ wins the rook.)

Rook pawn

The Lucena method also works with a rook pawn if the white rook is already on the fourth rank, the black rook is not on the file adjacent to the pawn, and White is to move.

Otherwise, the defending king must be cut off four files from the pawn, as in the diagram. This is not a true Lucena position since the king is cut off by more than one file. White wins:

1. Rc1 Ke7

2. Rc8 Kd6!

3. Rb8 Ra2

4. Kb7 Rb2+

5. Kc8 Rc2+

6. Kd8 Rh2!

7. Rb6+ Kc5

8. Rc6+! Kxc6

9. a8=Q+

and White has a won queen versus rook endgame – one that is easier to win than one where the rook is close to its king .

Similar positions may be drawn

Not all similar positions are wins. In this position, Black draws because he can safely check from the side. For this defense to work, there must be at least three files between the defending rook and the attacking king, and the defending king must be positioned such that it doesn't block the checks; that is, the defending king is on the "short side" of the pawn (the one with fewer files between the pawn and the edge of the board) . (See the "short side defense" at rook and pawn versus rook endgame for more details.)

Example from praxis

In this position from a 1999 game between Ulf Andersson

Ulf Andersson

Ulf Andersson is a leading Swedish chess player. FIDE awarded him the International Master title in 1970 and the Grandmaster title in 1972 .-Career:...

and Ralf Åkesson, White exchanges pawns in order to get to the Lucena position.

79. e4! dxe4

80. Rxe4 Kd7

81. Kg6

and Black resigned. White will reach a Lucena position: 81...Rg1+ 82.Kf7 Rf1 83.f6 Rf2 84.Kg7 Rg2+ 85.Kf8 Rf2 86.f7 Rg2 (a Lucena position) 87.Rd4+ Kc7 (if 87...Ke6 then 88.Ke8 wins) 88.Ke7 Re2+ 89. Kf6 Rf2+ 90.Ke6 Re2+ 91.Kf5 Rf2+ 92.Rf4 and White wins .

Conclusion

Rook and pawn endgames occur quite often in chess, about eight to ten percent of all games , . This position is very important since endgames may simplify to it. As it is a known win, endgames sometimes revolve around the player with the pawn trying to reach the Lucena position and the other player trying to prevent it.

There is an alternate method for winning this type of position that works only for pawns on the c-file through the f-file (see Rook and pawn versus rook endgame).

External links

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