Wednesday, October 11, 2006

Endgame Lab - Rooks - Lucena's Position

Salvio, 1634 - White to move and win

General Setup: Defender's King is pushed out of the pawn's way and cannot access the Queening square. Attacker's king is in front of his pawn, on the queening square.

The basic winning technique here is to "Build a Bridge" - interpose the attacking Rook between the checking Rook and attacker's King. Once that is achieved, the position is lost as the exchange of Rooks results in a won K+P vs. K endgame.

The general technique is as follows:
1) Superior side advances pawn to the 7th rank.
2) Superior side uses Rook to push defender's King out of the way.
3) Advance Attacker's Rook to the 4th Rank in preparation for 'Building a Bridge'.
4)Move attacker's King out of the way of his pawn.
5)Advance attacker's King toward defender's checking Rook.
6) Interpose attacker's Rook on the 4th rank to block checks - 'Building a Bridge'.

1.Rd1+ Kc7

"Superior side uses Rook to push defender's King out of the way."
Other moves lose as well: [ 1...Ke6 2.Ke8+-; 1...Kc6 2.Ke7 ( 2.Rd4 Kc5 3.Rd7 Kc6 4.Ke8 Rf2 5.Re7+-) 2...Re2+ 3.Kd8 Rf2 4.Rd7 Rf1 5.Ke8 Rf2 6.Re7+- ( 6.f8Q?? Rxf8+ 7.Kxf8 Kxd7=) ]

2.Rd4

"Advance Attacker's Rook to the 4th Rank in preparation for 'Building a Bridge'." [ if 2.Ke7?! Re2+ 3.Kf6 Rf2+ 4.Kg6 Rg2+ 5.Kh5 Rf2 does not work for white.]


2...Rg1 3.Ke7


"Move attacker's King out of the way of his pawn."

Re1+ 4.Kf6

"Advance attacker's King toward defender's checking Rook."

Rf1+ 5.Ke6 Re1+

[if 5...Rf2 6.Rd5 Rf1 7.Rf5+-]

6.Kf5 Rf1+

"Interpose attacker's Rook on the 4th rank to block checks - 'Building a Bridge'."

7.Rf4+-

"Building A Bridge". The point of 2. Rd4!

Of course, it is not as simple as it seems. Achieving a win from the Lucena Position is one thing; reaching the Lucena Position itself can be a completely different and difficult task, and we will examine that in our next Endgame Lab.

Source:Fundamental Chess Endings, Just the Facts!

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