The Endgame Tactician: Not Quite Lucena III
Not Quite Lucena positions feature the attacker's pawn on the sixth rank with his king in front of the pawn and are quite common in practice.
This is the final article in my series on Lucena. You may want to read through the earlier ones here, here, and here if you haven't already.
Today, we'll learn how to crush another inaccurate defense--a misplaced rook. Defenders goof in over 80% of such positions. So my advice to you is to be patient until an opportunity presents itself, and then be swift in exploiting it!
Mistake #3: The defending rook is less than 3 files away
Black to move. White is threatening Rg1+, initiating a Lucena maneuver, so Black must either initiate a passive defense with Rg1 or an active defense with Rb8+. By now, you know that an active defense is almost always the best plan.
1...Rb8+ 2.Kd7 Rb7+ 3.Kd6 Rb6+ 4.Kc7 and we reach this position:
An important point is that Black can't reposition his rook on the b-file. The only moves that stop White from queening this turn are:
4...Re6 5.Kd7 +-.
4...Kf7 5.Kxb6 +-.
White wins, because Black's rook was misplaced on the b-file.
Mistake #4: Thinking a misplaced piece is always fatal
Black to move. It's important to know that a misplaced rook or king is not always fatal, especially if the attacker's pawn is not too far advanced. In this position, Black can miraculously save himself with an active defense in spite of his misplaced rook.
1...Rb7+ 2.Kd6 Rb6+ 3.Kd7 Rb7+ 4.Kc6 and we reach this position:
As in the last position, two of Black's defenses fail:
4...Re7 5.Kd6 +-.
4...Kf6 5.Kxb7 +-.
But now, Rb2 or Rb3 or Rb4 draw! Moving along the b-file fell to e8=Q in the last position, but here e8=Q is impossible. What about e7?
4...Rb2 5.e7 Kf7!! 6.Re1 Ke8 and it's a Lucena no more.
I hope this series of articles has helped to deepen your understanding of one of the most important endgames in chess. I know I learned something.