Rook versus a knight: this is usually a draw. There are two main exceptions: (1) the knight is separated from the king and may be trapped and won, (2) the king and knight are poorly placed
I think White can win. There are lots of ways for Black to respond here, but White’s task is to keep the knight away from the Black king while driving it to capture. In the various ways I played this, I found some common positions that were important in keeping the knight and king separate.
Here is one sequence:
1. Re8 (keeping the knight from d8 and e7) 1. … Nd4 2. Re4 (guarding e6 and e2) 2. … Nc2 3. Kf3 Na3 (attempting an escape) 4. Rb4 (guarding b5 and c4) 4. … Nc2 5. Rc4 Na3 6. Rc5+ (again guarding b5 and c4) 6. … Kg6 7. Ke3 Nb1 8. Kd3 Na3 9. Ra5 Nb1 10. Kc2 and the knight is gone.
Here’s another sequence with similar themes:
1. Re8 Na7 2. Ke5 Nb5 3. Rc8 Kg5 4. Kd5 Kf5 5. Rc5 Na3 6. Kd4+ Kf4 (hoping to connect with the knight, if it can escape) 7. Kd3 Kf3 8. Ra5 Nb1 9. Kc2 and the knight is gone again.
Just as an aside, I often access this site while at school. (It’s a public school.) Recently, the school’s filters have prevented access to the readers’ comments section (the part that you are reading now) because of inappropriate content. That’s unfortunate, because I have been using it to coach some of my students in chess, always careful to screen comments myself first, but now I do not even have that option. I’m for free speech, but just offered this observation for anyone who might be interested.
“Just as an aside, I often access this site while at school. (It’s a public school.) Recently, the school’s filters have prevented access to the readers’ comments section (the part that you are reading now) because of inappropriate content. That’s unfortunate, because I have been using it to coach some of my students in chess, always careful to screen comments myself first, but now I do not even have that option. I’m for free speech, but just offered this observation for anyone who might be interested.”
Is this guy for real? Who uses live Internet to teach kids during school hours! Isn’t he afraid of “pop-ups” and accidentally opening disgusting pictures? I agree with patrick. Give your children good instruction without fear of Internet surprises. Use your head and then your chessboard! Please don’t be mad for my disagreeing with your methods. I too believe in free speech. It is better here than the USCF chatroom.
Like others, I think this is a win and I would start by 1.Re8 to keep the King and Knight separated. But honestly, I would not try to analyze this out from here to a win unless I had a large amount of time on my clock. The search tree is just too dense. If anyone has a foolproof heuristic, please pass it on to the rest of us!
I have a student who once got into a position like this with the N vs the R. She should have lost, as the N at one point got separated from the R; but her opponent did not capitalize on this and she eventually forked him to secure the draw.
I don’t have a foolproof heuristic (yes, I had to look that up), but I’ve been approaching this the same way I learned the knight and bishop endgame (whose search tree is also rather dense): I’ve been placing the pieces all over the board and seeing if I could force a win. Not always, with confidence, but I’m beginning to see some patterns develop and have gotten better at recognizing where I’m going with it all.
patrick henry, et al.:
Sorry about the offense my comments caused, along with the misunderstanding. I was expressing regret about something, not prescribing anything for anyone.
Just to fill in the missing info: of course we use a lot of things for teaching chess: boards and pieces, books, magazines, games, puzzles, and all the other things you would guess. Susan Polgar’s chess blog, with its puzzles and excellent contributions from readers, is an obvious choice. It’s a pleasure to peruse the comments and find things that would be beneficial to the kids.
No, we don’t scan the internet with the kids. Ethical and legal constraints prevent this (which non-teachers would not necessarily anticipate), plus, as anyone who read my comments carefully would realize, the filters on our school computers would prevent offensive content anyway.
The point is that I cannot access the site anymore, and I once could. I don’t know what changed: the content or the filters. Maybe it was just the filters. I’ve never really understood the purpose of the more caustic comments posted here, especially those well out of proportion to the issue, but that’s just folks.
Rook versus a knight: this is usually a draw. There are two main exceptions: (1) the knight is separated from the king and may be trapped and won, (2) the king and knight are poorly placed
Win for white! Re8 starts it off
I think the idea is to trap the knight starting with Re8. The Black King can’t move so the Knight is forced to move.
I think White can win. There are lots of ways for Black to respond here, but White’s task is to keep the knight away from the Black king while driving it to capture. In the various ways I played this, I found some common positions that were important in keeping the knight and king separate.
Here is one sequence:
1. Re8 (keeping the knight from d8 and e7)
1. … Nd4
2. Re4 (guarding e6 and e2)
2. … Nc2
3. Kf3 Na3 (attempting an escape)
4. Rb4 (guarding b5 and c4)
4. … Nc2
5. Rc4 Na3
6. Rc5+ (again guarding b5 and c4)
6. … Kg6
7. Ke3 Nb1
8. Kd3 Na3
9. Ra5 Nb1
10. Kc2 and the knight is gone.
Here’s another sequence with similar themes:
1. Re8 Na7
2. Ke5 Nb5
3. Rc8 Kg5
4. Kd5 Kf5
5. Rc5 Na3
6. Kd4+ Kf4 (hoping to connect with the knight, if it can escape)
7. Kd3 Kf3
8. Ra5 Nb1
9. Kc2 and the knight is gone again.
Just as an aside, I often access this site while at school. (It’s a public school.) Recently, the school’s filters have prevented access to the readers’ comments section (the part that you are reading now) because of inappropriate content. That’s unfortunate, because I have been using it to coach some of my students in chess, always careful to screen comments myself first, but now I do not even have that option. I’m for free speech, but just offered this observation for anyone who might be interested.
Why are you using a chess news blog to teach chess? Pull out your chessboard and teach chess. Leave us big kids alone adolf…
“I’m for free speech, but just offered this observation for anyone who might be interested.”
You liar!
Log off loser!
“Just as an aside, I often access this site while at school. (It’s a public school.) Recently, the school’s filters have prevented access to the readers’ comments section (the part that you are reading now) because of inappropriate content. That’s unfortunate, because I have been using it to coach some of my students in chess, always careful to screen comments myself first, but now I do not even have that option. I’m for free speech, but just offered this observation for anyone who might be interested.”
Is this guy for real? Who uses live Internet to teach kids during school hours! Isn’t he afraid of “pop-ups” and accidentally opening disgusting pictures? I agree with patrick. Give your children good instruction without fear of Internet surprises. Use your head and then your chessboard! Please don’t be mad for my disagreeing with your methods. I too believe in free speech. It is better here than the USCF chatroom.
“I think the idea is to trap the knight starting with Re8.”
I don’t. The idea is obviously to see how many know how to use tablebase. It’s a trick question for beginners.
Like others, I think this is a win and I would start by 1.Re8 to keep the King and Knight separated. But honestly, I would not try to analyze this out from here to a win unless I had a large amount of time on my clock. The search tree is just too dense. If anyone has a foolproof heuristic, please pass it on to the rest of us!
I have a student who once got into a position like this with the N vs the R. She should have lost, as the N at one point got separated from the R; but her opponent did not capitalize on this and she eventually forked him to secure the draw.
tim:
I don’t have a foolproof heuristic (yes, I had to look that up), but I’ve been approaching this the same way I learned the knight and bishop endgame (whose search tree is also rather dense): I’ve been placing the pieces all over the board and seeing if I could force a win. Not always, with confidence, but I’m beginning to see some patterns develop and have gotten better at recognizing where I’m going with it all.
patrick henry, et al.:
Sorry about the offense my comments caused, along with the misunderstanding. I was expressing regret about something, not prescribing anything for anyone.
Just to fill in the missing info: of course we use a lot of things for teaching chess: boards and pieces, books, magazines, games, puzzles, and all the other things you would guess. Susan Polgar’s chess blog, with its puzzles and excellent contributions from readers, is an obvious choice. It’s a pleasure to peruse the comments and find things that would be beneficial to the kids.
No, we don’t scan the internet with the kids. Ethical and legal constraints prevent this (which non-teachers would not necessarily anticipate), plus, as anyone who read my comments carefully would realize, the filters on our school computers would prevent offensive content anyway.
The point is that I cannot access the site anymore, and I once could. I don’t know what changed: the content or the filters. Maybe it was just the filters. I’ve never really understood the purpose of the more caustic comments posted here, especially those well out of proportion to the issue, but that’s just folks.
Re8 works best for the win, restraining the Black Knight from e7, but Rg7 also works for the win, but takes a lot longer.
Excellent teaching puzzle!
I knew the basics, but had to work at it a bit to cement the win.
Peter / chesstoplay
Either king or rook can dominate knight when separated by two diagonal squares. One does not need a tablebase to know that.
It’s funny that Kramnik, the greatest endgame player alive, missed this idea vs. Topalov (in game 2? of the WC: …Re3! vs the actual …Re1)