Sep-25-17
 | | g15713: Diagram 38A on page 61 of Practical Rook Endings by Edmar Mednis is a typically drawn position when the defending rook is behind the passed a- pawn.
click for larger viewThis position after Black’s 36th move 36…h6 was analyzed by popular and respected chess writer and American International Grandmaster, Edmar Mednis (1982), Practical Rook Endings, Chess Enterprises, ISBN 0-931462-16-9. Unfortunately, the book is out of print but used copies are still available on the Internet at Amazon or Bookfinder at about $30 and up. If one can find a copy at a decent price, buy it! - it's a little gem. Here is an excerpt from Mednis:
<“White is ahead a passed a-pawn, but his Rook is disadvantageously placed in front of the pawn. On the other hand, Black’s Rook has the ideal, active position behind White’s passed pawn. From this location it can both stop the a-pawn and attack the Kingside pawns if White’s King would decide to head for the Queenside. With the a-pawn and the respective Rook placements, endings where the Kingside pawns are from zero to three on each side are drawn unless the defending side’s pawns are weak and exposed to attack by White’s King. Where each side has four pawns on the Kingside, White’s winning chances are significantly increased as he is often able to create a weakness in Black’s pawn formation by advancing his own Kingside pawns.
From positions such as Diagram 38A, White can readily run his a- pawn to a7. However, this will not win, because his King then cannot find a hiding place on the Queenside and thus White’s Rook cannot be liberated from the a8 spot. Black simply keeps his King on g7 or h7 and White can’t progress. With the pawn on a7, >White< can’t win even if he gets a passed g- or h-pawn, because these can’t dislodge Black’s King from g7/h7. To win with an extra pawn on the Kingside, this must be a passed e- or f- pawn. Because the pawn on a7 takes away hiding places from White’s King, the usual winning try consists of pushing it to a6 and then heading with the King to a7. To draw Black must in the meantime capture at least one of White’s Kingside pawns and attempt to fashion a passed pawn himself. Then when White’s a-pawn plus King will force Black to give up his Rook, White’s King will be far away from the Kingside and Black’s King plus passed pawn will achieve a draw.”> Continuing with the game continuation:
46 gxf5+ Kxf5
Position after exchange of pawns, White to move 
click for larger viewAccording to FinalGen, a chess endgame tablebase generator for Windows, this is a draw for Black. Those with Lomonosov Endgame Tablebases for 7 pieces can verify this. 47 Ra8 Kg6!
<"Some care is required in almost all positions. Black must ensure that if White plays a7 his King can get to g7 or h7. Losing would be 47...Ra2?? as after 48 a7 a devastating check by White’s Rook cannot be prevented.”> 48 Kg4 Ra4+
49 Kf3 Kh5!
<“Here too the King is safe from checks. If White’s King now heads for the Queenside, Black’s King will capture the h-pawn for a certain draw.
Therefore :”>
50 Ke3 Kh4 Draw. |
Kibitzing
