White is winning. 1. a7 Rb2+ 1. … Ra2 2. Ba6 and White will escape from vertical checks by zig-zagging down the b- and c-files. 2. Bb5! Rxb5+ 2. … Ra2 3. Ba6 and White will escape from checks as in the above line. 3. Ka6 and White will Queen with check, eventually winning the Q vs. R endgame.
And, now, black can check the king or get behind the a-pawn. Let’s take each in order:
1. …..Rb2
Now, I have had the benefit of actually having to play this kind of endgame more than once, so I don’t have to actually think about this at all:
2. Bb5!
The bishop is untouchable. The key feature here is that white will queen with check, so it will do black no good to take at b5, because white plays Ka6 and there is no square from which black can cover a8 safely, and drawing back far enough away on the b-file to skewer the king won’t work due to the queening check I mentioned. So, in this line, black must now try to get behind the pawn:
2. …..Ra2 3. Ba6
Now, one might think all is well for white- he can walk down the b- and c-files as the black rook checks repeatedly from b2 and c2, and if black tries this, that is exactly what the white king will do via c6, b5, c4, and b3. This, of course works because the bishop covers c8 preventing Rc8, and the pawn covers b8 preventing Rb8. However, there is one little wrinkle in this position that white must deal with:
3. …..Rg2
Now, if white carelessly plays a8(Q), black replies with Rg8 blocking the check and attacking the queen, and the only square for the new white queen is a7 and she will be skewered on the next move of black’s rook when he checks from g7. Now, how does white deal with this? There is only one way- get prepared to block with bishop at c8:
4. Kb8! Rb2 (Rg8 5.Bc8 wins) 5. Kc7!
Now, Rg2 won’t work since the new white queen will have access to any square along the h1/a8 diagonal, especially h1 where the queen moves with check. So black is left with the checks from a distance:
5. …..Rc2 6. Kb2 Rb2 7. Kc5 Rc2 8. Bc4 and now a2 is not longer available to the black rook, and he has no safe squares from which to deliver another check.
So, are things materially different if black plays to a2 on the first move? Well, no:
1. a7 Ra2
Here, again, Rg2 won’t work since the new white queen has all of the a-file to maneuver on, especially a1 from which she can deliver a check on the black king.
2. Ba6 and we have already seen this position earlier, and it was lost.
Now, for one last item- what happens if white cannot queen with check? Let us suppose the black king was off the 8th rank and at g7- can white win now? The answer is, no:
1. a7
Here, black must avoid Ra2, as this loses to Ba6:
1. …..Ra2?? 2. Ba6 Rf2
This is the previous line’s analogous move of Rg2:
3. Kb8
And, as before, the bishop is going to block any check from f8, and black cannot prevent the pawn from queening. No, in this alternate position, black must play Rb2 on his first move- he must never allow white to play the bishop to a6:
1. …..Rb2
And the white king will have to leave the b-file since, now, 2.Bb5 doesn’t work since black can take at b5 and retreat the rook to b3/2/1 when white plays Ka6. Playing the white king to a8 just means white can’t queen, and playing the king to c7, c8, or c6 just loses the pawn when black plays Ra2 followed by Ra7.
Black has to exchange the rook for the pawn in order to draw. Both ways to do this are stopped by the bish: …Rh7+ can’t be played because of BxR; and …Ra2 doesn’t work because of Ba6, and the pawn queens, as after more rook checks, white walks the king toward the rook on the b and c files, and the Bishop covers the c8 square and the pawn the b8 square, so the rook can’t come down and stop the pawn that way, either.
a7 forces Ra2 Ba6 and then following the spite checks white marches his king down through the b and c files. Since both b8 and c8 are covered by the pawn and bishop, black can’t stop white from queening.
The alternatives are a7 or Bc4 (trying to prevent black from sacking his rook for the pawn). a7: Then not Ra1 Ba6, but Rb2+ followed by Ra1, holds draw. Bc4: Best for black now seems to be Rh7+ followed by Rh5 and Ra5. Seems to be a draw.
White is winning.
1. a7 Rb2+
1. … Ra2 2. Ba6 and White will escape from vertical checks by zig-zagging down the b- and c-files.
2. Bb5! Rxb5+
2. … Ra2 3. Ba6 and White will escape from checks as in the above line.
3. Ka6 and White will Queen with check, eventually winning the Q vs. R endgame.
1. a7 then if 1… Ra2 2.Ba6 wins. If 1… Rb2+ then 2. Bb5. Then if 2… Rxb5+ then 3. Ka6 or of 2… Ra2 3.Ba6 seems to win.
Well, the first move has to be a7:
1. a7
And, now, black can check the king or get behind the a-pawn. Let’s take each in order:
1. …..Rb2
Now, I have had the benefit of actually having to play this kind of endgame more than once, so I don’t have to actually think about this at all:
2. Bb5!
The bishop is untouchable. The key feature here is that white will queen with check, so it will do black no good to take at b5, because white plays Ka6 and there is no square from which black can cover a8 safely, and drawing back far enough away on the b-file to skewer the king won’t work due to the queening check I mentioned. So, in this line, black must now try to get behind the pawn:
2. …..Ra2
3. Ba6
Now, one might think all is well for white- he can walk down the b- and c-files as the black rook checks repeatedly from b2 and c2, and if black tries this, that is exactly what the white king will do via c6, b5, c4, and b3. This, of course works because the bishop covers c8 preventing Rc8, and the pawn covers b8 preventing Rb8. However, there is one little wrinkle in this position that white must deal with:
3. …..Rg2
Now, if white carelessly plays a8(Q), black replies with Rg8 blocking the check and attacking the queen, and the only square for the new white queen is a7 and she will be skewered on the next move of black’s rook when he checks from g7. Now, how does white deal with this? There is only one way- get prepared to block with bishop at c8:
4. Kb8! Rb2 (Rg8 5.Bc8 wins)
5. Kc7!
Now, Rg2 won’t work since the new white queen will have access to any square along the h1/a8 diagonal, especially h1 where the queen moves with check. So black is left with the checks from a distance:
5. …..Rc2
6. Kb2 Rb2
7. Kc5 Rc2
8. Bc4 and now a2 is not longer available to the black rook, and he has no safe squares from which to deliver another check.
So, are things materially different if black plays to a2 on the first move? Well, no:
1. a7 Ra2
Here, again, Rg2 won’t work since the new white queen has all of the a-file to maneuver on, especially a1 from which she can deliver a check on the black king.
2. Ba6 and we have already seen this position earlier, and it was lost.
Now, for one last item- what happens if white cannot queen with check? Let us suppose the black king was off the 8th rank and at g7- can white win now? The answer is, no:
1. a7
Here, black must avoid Ra2, as this loses to Ba6:
1. …..Ra2??
2. Ba6 Rf2
This is the previous line’s analogous move of Rg2:
3. Kb8
And, as before, the bishop is going to block any check from f8, and black cannot prevent the pawn from queening. No, in this alternate position, black must play Rb2 on his first move- he must never allow white to play the bishop to a6:
1. …..Rb2
And the white king will have to leave the b-file since, now, 2.Bb5 doesn’t work since black can take at b5 and retreat the rook to b3/2/1 when white plays Ka6. Playing the white king to a8 just means white can’t queen, and playing the king to c7, c8, or c6 just loses the pawn when black plays Ra2 followed by Ra7.
It’s a win. White can play:
1 a7
Black has to exchange the rook for the pawn in order to draw. Both ways to do this are stopped by the bish: …Rh7+ can’t be played because of BxR; and …Ra2 doesn’t work because of Ba6, and the pawn queens, as after more rook checks, white walks the king toward the rook on the b and c files, and the Bishop covers the c8 square and the pawn the b8 square, so the rook can’t come down and stop the pawn that way, either.
it’s a win, supposing one knows ho to win with queen against rook in the endgame (i don’t):
1. a7 Rb2+
2. Bb5 Rxb5+
3. Ka6 Rb1
4. a8Q+
greets, jan
Hello
White wins.. I saw a similar problem in the past.
1. a7 , Rb7+
2. Bb5!!, Rxb5+
3. Ka6 winning because blacks can´t avoid that the white pawn becomes queen
Greetings from Spain
The old QvR endgame emerges after:
1. a7 Rb2+ (1. … Ra2 2. Ba6 Rb2+ is the same)
2. Bb5 Rxb5+
3. Ka6
This is a win for White, but is rather complicated.
1.a7 Rb2+(1…Ra2 2.Ba6 wins) 2.Bb5! Rxb5+ 3.Ka6 wins for white.
1.a7! Rb2+
1…Ra2 2.Ba6! Rb2+ 3.Kc6 and the rook will run out of checks since it can’t acceed to the seventh rank
2.Bb5!! Ra2
2….RxB check 3.Ka6 check to the rook 🙂
3.Ba6 +- with the aforementioned win
1.a7 Rb2+ 2. Bb5 Rxb5 3. Ka6 and promotes with check
if 1…Ra2 2. Ba6
1.a7 Rb2+ 2. Bb5 Rxb5 3. Ka6 and promotes with check
if 1…Ra2 2. Ba6
1.a7 Rb2+ 2.Bb5 Rxb5+ 3.Ka6 looks like the main variation. I don’t see any way for Black to improve. For example, 1…Ra2 is answered by Ba6. Phil
a7 Rb2
Bb5 Rb5
Ka6
White wins because of the unfortunate position of Black’s king. I see two variations:
(A) 1…Ra2 2.Ba6 Rb2+ 3.Kc6 Rc2+ 4.Kb5 Rb2+ 5.Kc4 Rc2+ 6.Kb3 and the pawn promotes.
(B) 1…Rb2+ 2.Bb5! Rxb5+ 3.Ka6 and wins, since the pawn queens with check. Otherwise Black could draw with 3…Rb1 and 4…Ra1+.
1. a7 Rb2+ (1…Ra2 2.Ba6 same)
2. Kc7 Ra2
3. Kb6 Rb2+
4. Bb5 Ra2
5. Ba6 Rb2+
6. Kc7 Rc2+
7. Kd7 Rd2+
8. Ke7 white wins
OR
a7 forces Ra2
Ba6 and then following the spite checks white marches his king down through the b and c files. Since both b8 and c8 are covered by the pawn and bishop, black can’t stop white from queening.
It’s a win for white after 1. a7
For instance:
1. a7! Ra2
(1… Rb2+
2. Bb5 Rxb5+
3. Ka6 Rf5
(3… Rb1 4. a8=Q+)
4. a8=Q+ +-)
2. Ba6 Rg2
3. Kb8!
( 3. a8=Q+? Rg8!
4. Qa7 Rg7+ =)
3. … Rg8+
4. Bc8 +-
Correction: after a7, Rb2+; white blocks with the bish Bb5 so that the king can get to a6 and cut off the rook if RxB.
Win!
1, a7 Ra2
2, Ba6 Rb2+
3, Kc6 Rc2+
4, Kb5 Rb2+
5, Kc4 Rc2+
6, Kb3 and over, white pawn will become a Queen!
Best from Hungary
a7, ra2, ba6 wins
han
This is a win for white.
1.a7 Ra2
2.Ba6 Now the a-pawn covers b8 and the bishop covers c8. So if black checks wihite just zig-zags his K to the 3rd rank.
1.a7 Rb2+
2.Bb5 Rxb5 (Ra2 tranposes to above)
3.Ka6 and the pawn queens.
The alternatives are a7 or Bc4 (trying to prevent black from sacking his rook for the pawn).
a7:
Then not Ra1 Ba6, but Rb2+ followed by Ra1, holds draw.
Bc4:
Best for black now seems to be Rh7+ followed by Rh5 and Ra5.
Seems to be a draw.