Saturday, June 6, 2015

Practical Rook Endgames 01: Lucena and Philidor

The chess blogosphere recently went abuzz over a small bumper crop of the endgame involving two knights versus a pawn. Somehow this endgame doesn't get my obsessive juices flowing, so I'm going to take a pass for now.

A year ago, I compiled the games of a friend who had passed away. While he was known in our club to be a fantastic tactician, one thing that really stood out in going over his games was that he was pretty good at grinding points out of rook endgames. I consider myself decent at endgames but with still lots to learn. Lately, rook endgames keep popping up in my games and through a little knowledge and more than a little luck, I have gotten more than my share of points in them.

Since I don't have a scheduled club game for a while, my project for the next few weeks is to try to blog about rook endgames. You'll notice that the title of this post is "Practical Rook Endgames 01". This is a conceit. I have barely blogged once this year and now I expect to hit double digits in this topic alone. Better get started.

No discussion about rook endgames should start without the Lucena and Philidor positions, so I thought I'd rehash their basic lessons first.

Lucena

I have blogged about Lucena before, here and here, the latter post being my most popular, likely because the key word Moria baits a lot of unwitting Lord of the Rings googlers.

    Lucena Factual Elements:
  • Material is Rook plus Pawn versus Rook
  • Having a Lucena position means having a win
  • Pawn cannot be a rook pawn
  • Defending king cut off by attacking rook (no Philidor defense)
  • Pawn has reached its 5th rank (no frontal defense)
  • Defense does not have lateral checking distance of at least 3 empty squares between rook and pawn (no long side defense)
  • Key strategy is to "build a bridge" with rook to the 4th rank just before the king runs out from behind the pawn

Position 1: Lucena Begins

White's first maneuver is to escort his pawn to the seventh rank. 1.Kf5 Rf1+ 2.Kg6 Re1 3.Kf6 Rf1+ 4.Ke7 Re1 5.e6 Re3 6.Kf7 Rf3+ 7.Ke8 Re3 8.e7

Position 2: Black Rook Chooses How to Lose

Now Black has some choices on how he wants to lose. White's simplest plan could be Rf2 and then Kf7 and then e8=Q with a timely Rd2+ if the Black King gets too close. White can even allow a non-checking Rxe8 if it's immediately followed by Rd2+, winning the rook.

Variation 1: Black could counter this plan now with 8...Rf3 but White switches to 9.Rc2+, forcing the Black King to make a choice.

Position 3: Black King Chooses How to Lose

Variation 1A: 9...Kb7. And now, the key position of the Lucena:

Position 4: Lucena's Key Position

Build a bridge with Rc4!

10.Rc4! White's king is now ready to come out through d7: 10...Kb6 11.Kd7 Rd3+ 12.Ke6 Re3+ 13.Kd6 Rd3+ 14.Ke5 Re3+ 15.Re4

Position 5: Lucena Bridge Built!

Notice that if Black trades rooks, his king cannot catch the pawn before it queens. This is important to how the rook bridge works. So the move 9.Rc2+ was not an insignificant check. Now Black can't stop the pawn from queening and White wins.

Going back a couple of moves, instead of Black mindlessly checking the king, on move 13...

Position 6: Lucena Bridge shortens

13...Re1 14.Rb4+ Ka5 15.Rd4 Kb5 16.Rd5 Sometimes, White has to shorten the bridge. Black is powerless to prevent Re5. As long as the defending king is far away, this maneuver should work.

Variation 1B: From Position 3, instead of 9...Kb7, how about 9...Kd6? Then the White King uses the Black King as cover and plays 10.Kd8

Position 7: Defending King blocks his own Rook

The White king is safe in the east from 10...Rf8+ 11.exf8=Q, safe in the south because 10...Rd3 11.e8=Q achieves nothing, and safe in the west 10...Ra3 11.e8=Q Ra8+ 12.Rc8.

Variation 1C: From Position 3, suppose Black wants to chase the bridge away. 9...Kb6 10.Rc4 Kb5

Position 8: Attempted Bridge Sabotage

White builds the bridge anyway, before the king is there to use it. 11.Re4 Kc5 12.Kd7 Rf7 13.Kd8 and Black can only sacrifice his rook to stop the pawn.

Variation 2: From Position 2, Black keeps his king in the fight with 8...Rc3 9.Rf2! White simply creates cover for Kf7, the white King's other path to come out from e8. 9...Re3 10.Kf7 Kd7 11.Rd2+ Kc7 12.e8=Q and White wins. This less flamboyant method of winning is necessary to know for knight pawns, so here is a diagram similar to Position 2, but with everything shifted two files to the right:

Position 9: Knight Pawn Mundanity

1...Re3 2.Rh2 Rg3 3.Kh7 Kf7 4.Rf2+ Ke7 5.g8=Q Rh3+ 6.Kg7 Rg3+ 7.Kh8 Rh3+ 8.Qh7+ and White wins. If White attempted to build a bridge, Black can ignore it: 1...Re3 2.Rf4 Re1 3.Kh7 Rh1+ 4.Kg6 Rg1+ 5.Kh6 Rh1+ 6.Kg5 Rg1+ and now White has to go all the way back to Kg8 because 7.Rg4?? Rxg4+ 8.Kxg4 9.Kf7 draws. The defending king was left too close to the pawn.

Philidor

I have bloogged about Philidor before, here and here.

    Philidor Factual Elements
  • Material is Rook plus Pawn versus Rook
  • Having a Philidor position means having a draw
  • Defending king has reached the queening square, not cut off

Position 10: Philidor

The defender would do well to start the rook blockade on his third rank. Indeed, the Philidor position is also known as the Third Rank Defense. As soon as the pawn reaches this rank (6th rank from the pawn's point of view), the rook goes to his eighth rank to start endless harassing checks in the back against the attacking king. 1.Ra7+ Ke8 2.e6 Rb1 3.Kf6 Rf1+ The White King has nowhere to hide from checks, thanks to the Black King and in part to his own pawn.

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