 |
| Black has just played 51...Ke5-f6 |
*****
*****
*****
*****
*****
*****
*****
I suspect many players will know, or instinctively feel, the position is drawn, and that is confirmed by the Syzygy endgame tablebase.
As a matter of fact the same position, but without a black pawn, is also drawn.
 |
| Draw! |
*****
*****
*****
*****
*****
But, as grandmaster Spyridon Skembris pointed out, it is one thing knowing a position is drawn, quite another actually drawing it.
*****
*****
*****
*****
But, as grandmaster Spyridon Skembris pointed out, it is one thing knowing a position is drawn, quite another actually drawing it.
From the first diagram, my game with black against Martin Schaefer (1921) continued 52.Rb6+ Kf7 (an only-move, but an obvious one) 53.Rh6.
 |
| Six moves draw, but I managed to play one that does not |
*****
*****
*****
*****
53...Rg7?
The drawing moves are ...Ke7, ...Ra8, ...Rb8, ...Rc8, ...Rd8 and ...Re8.
 |
| White to play and win |
*****
*****
*****
*****
54.Kh5
Winning is 54.Rh8! The point is the black rook cannot sensibly move, and 54...Kf6 runs into 55.Ra8 (other moves also win), eg 55...Ke5 56.Ra6 Rg8 57.f6 Rg6 58.f7!
Winning is 54.Rh8! The point is the black rook cannot sensibly move, and 54...Kf6 runs into 55.Ra8 (other moves also win), eg 55...Ke5 56.Ra6 Rg8 57.f6 Rg6 58.f7!
54...Rg8
Another only-move, but not difficult to find.
55.Rb6 Rh8+
Also drawing is 55...Ke7.
56.Kg4 Rh4+ 57.Kg3 Rf4 ½–½
 |
| The ending of rook, bishop's pawn and rook's pawn (pawns on the same wing) versus rook is widely covered in endgame books |
*****
*****
*****
*****
Among such books is Rook Endings by Grigory Levenfish and Vasily Smyslov.
I have the 1989 Batsford algebraic edition, but the original Russian edition is much older (Levenfish died in 1961).
The authors wrote: "When Marshall drew such an ending at San Sebastian 1911 against Rubinstein, theoreticians set about a detailed analysis of it.
"Spielmann, Rabinovich, Belavenets, Maizelis, Zek, Keres and finally Botvinnik together with Ragozin and Flohr discovered many interesting ideas.
"All the same, far from everything is clear in the assessment of this ending."
Nowadays six-piece tablebases can tell us which positions are drawn, and which are won, but more important for the practical player is the how of such positions.
 |
| This position occurs twice in ChessBase's 2023 Mega database |
*****
*****
*****
*****
In the Mega23 games it is White to move, but the position is winning for White even with Black to play, analysis being credited to Sergey Belavenets, a Soviet master killed in World War Two.
White threatens to win by pushing either pawn, eg 2.h7+ Kh8 3.f7 Rg1+ 4.Kh4 Rh1+ 5.Kg3 Kg7 6.Rb8 etc.
Black can delay this with 1...Rg1+, but to no avail in the long run, eg 2.Kf5 Rf1+ 3.Ke6 Re1+ 4.Kd6 (not 4.Kd7 Kf7 as that is a tablebase draw) Rd1+ (or 4...Rh1 5.h7+ Kf8 6.h8=Q+ etc) 5.Ke7 Re1+ 6.Kd8 Rd1+ 7.Rd7 Rf1 8.h7+ Kh8 9.Rd6 Kxh7 10.Ke8 Kg8 11.Re6 Rf2 12.Ke7 Rf1 13.Re2 Rf3 14.Rg2+ etc.
According to Rook Endings, Black's problem in the Belavenets position is having the king confined to the back rank.
Black therefore needs to keep the king active, and in particular to avoid the position reached in the last diagram above.
 |
| White has just captured on h4 in Igor Bondarevsky - Paul Keres, Leningrad & Moscow 1939 |
*****
*****
*****
*****
Komodo14.1 at first reckons White is winning, but later fluctuates between "winning" and giving White the upper hand. Stockfish15.1 calls the position drawn, which Syzygy confirms.
58...Rg1 59.Kf3 Ra1
Levenfish & Smyslov quote Mikhail Botvinnik as stating the black rook is best placed on a1, "but sometimes it has to be placed on f1 or h6."
60.Rg4 Ra3+ 61.Kg2 Rb3 62.f3 Rb2+ 63.Kg3 Rb1
But not ...Rb3? or ...Ra2? as Syzygy shows both moves lose to pushing the h pawn, eg 63...Ra2? 64.h4 Ra1 65.h5 Rh1 66.Rh4 Rg1+ 67.Kf2 Ra1 68.h6 Ra8 69.h7 Rh8 70.f4 Kg6 71.Kf3 Rxh7 72.Rxh7 Kxh7 73.Ke4 (an only-move - the white king needs to reach e6, f6 or g6 to win) Kg6 74.Ke5 Kg7 75.Kf5 etc.
64.h4 Rg1+ 65.Kh3 Rb1
Not 65...Rh1+? as after 66.Kg2 the black rook has to move, and again the h pawn can be pushed to victory.
66.Kg2 Rb2+?
The temptation of checking! Keres had five drawing moves: ...Rb6, ...Rb7, ...Rb8, ...Kf6 and ...Ke6!?
67.Kg3 Rb1 68.h5 Rb6
If 68...Rh1 then 69.Rh4 etc.
69.Rh4 Rh6 70.Ra4 Rb6
 |
| White to play and win |
*****
*****
*****
*****
71.Ra5+?
The check temptation again. Both Rh4 and Rg4 win, eg 71.Rh4 Rh6 72.Rf4+ Kg5 73.Rg4+ Kf5 74.Kh4 Ra6 75.Rg5+ Kf4 76.Rg8 Kf5 77.Rf8+ Ke6 78.Kg4 Ra4+ 79.Rf4 Ra1 80.h6 Rh1 81.Kg5 Rg1+ 82.Rg4 Rh1 83.f4 Ke7 84.f5 Kf7 85.f6 Rh2 86.Rg1 Rh3 87.Ra1 Rg3+ 88.Kh4 Rg2 89.h7! (the only winning move) Rh2+ 90.Kg5 Rxh7+ (or 90...Rg2+ 91.Kf4 Rf2+ 92.Kg3 etc) 91.Ra7+ Kg8 92.Rxh7 Kxh7 93.Kf5 (93.Kh5 also wins) Kg8 94.Kg6 Kf8 95.f7 etc.
71...Kf6 72.Kg4 Rb1 73.Ra6+ Kg7
An only-move, but from now on Black's drawing moves are much easier to find.
74.f4 Rg1+ 75.Kf5 Rh1 76.h6+ Kh7 77.Re6 Rb1 78.Ke5 Rb5+ 79.Ke4 Rb1 80.f5 Rg1 81.Kf4 Rg2 82.Ke5 Ra2
Bondarevsky played on for another 15 moves before the game eventually ended in stalemate.
If such strong players as Keres and Bondarevsky can get it wrong, the danger signals are certainly there for the rest of us.
The game Paul Keres - Alexey Sokolsky, Chigorin Memorial (Moscow) 1947, is another warning of what can go wrong.
 |
| White has just captured on h4 |
*****
*****
*****
*****
Once again Stockfish15.1 recognises the position as drawn, but Komodo14.1 is convinced White is winning.
60...Kf5 61.Rg4 Rh8+ 62.Kg3 Ra8 63.h4 Ra1?
Rook Endings quotes Botvinnik as recommending 63...Rh8, and only after 64.Rg5+ Kf6 65.Kg4 Ra8 66.h5 "going onto the defensive with 66...Ra1, as White is unable to get his rook behind the h pawn."
Syzygy shows 63...Kf6 and 63...Ke6!? also draw.
64.h5
The same idea as could have occurred in Bondarevsky - Keres. The white rook can get behind the h pawn and so the game is won.
(to be continued)
No comments:
Post a Comment