The Endgame Tactician: Not Quite Lucena II
Today, we'll learn how to crush a couple inaccurate defenses. 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 #1: The defending king is on the eighth rank
Black to move. Black has a few defenses he can try:
1...Kg7 - Black places his king where it belongs, on the sixth or seventh rank. The refutation is simply 2.Rg2+!, beginning a Lucena maneuver.
1...Ra7+ - Black's best try is an active defense. This would work if the Black king were on the sixth or seventh rank, but now it fails to 2.Kf6 Ra6 3.Rd8+ Kh7 and with the Black king more than one file away, the win is inevitable. An important point is that 2...Kf8 was impossible due to 3.Rd8#.
1...Rg1 - Black mount a passive defense, preventing a check on the g-file. In rook endings, passive defenses usually fail and this is no exception. 2.Ke8 Kg7 3.e7 and now either 4.Kd7 or 4.Rg2+ is unstoppable and wins.
White wins, with Black to move, if his rook's on any of the green squares. These squares (a) allow White to initiate a Lucena maneuver if Black moves his king to g7 and (b) prevent 2...Kf8 due to 3.Rd8#.
Mistake #2: The defending king is on the fifth rank
1...Kg6 - Black places his king where it belongs, on the sixth or seventh rank. The refutation is simply 2.Rg2+!, beginning a Lucena maneuver.
1...Ra7+ - Black's best try is an active defense. This would work if the Black king were on the sixth or seventh rank, but now it fails to 2.Kf8 Ra8+ 3.Kf7 Ra7+ 4.e7. The problem is, White's rook must stand alone, and a strong defense usually requires coordination between the rook and king.
1...Rg1 - Black mount a passive defense, preventing a check on the g-file. In rook endings, passive defenses usually fail and this is no exception. 2.Ke8 Kg6 3.e7 and now either 4.Kd7 or 4.Rg2+ is unstoppable and wins.
White wins, with Black to move, if his rook's on any of the green squares. These squares allow White to initiate a Lucena maneuver if Black moves his king to g6.
I hope you enjoyed this article and learned something, too. :)