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Secrets of Trapping Pieces: Knight Trapped by King + Piece

KevinSmithIdiot

Updated: Oct 18, 2024, 4:40 PM | 2

The primary purpose of this blog is to allow you to test your skills at trapping Knights with a King, usually assisted by another piece. It is common to find the King collaborating with another piece to trap a Knight. But under the correct circumstances the King can trap a Knight by Himself. So, we will discuss that as well.

Confession (no booth required because I'm neither a super-GM nor Catholic). This is a previously published article from the summer of 2023 that was unfortunately deleted. Fortunately, I was able to scrape most of the information from the web before it disappeared forever and am now recreating it. And improving it where advisable without exceeding my patience! Lesson learned? What this really lets me know is that I should store copies of all my blogs under a separate area, perhaps as "Drafts" with slightly altered names (e.g., "Draft") that serve purely as backups. Although that word always makes me think of a beer...or two. Just to fuel me through the process of recreating prior material, you understand.

Before moving on to the puzzles I establish some base cases to offer would-be solvers some guidelines when developing plausible solutions. In the diagram below we look at four simple scenarios. Note that the King could also be in direct contact with the Knight by placing the King on b2, b7, g2 or g7. But the diagram offers more general cases. Note that this type of Knight entrapment is encountered rather frequently, as you can observe yourself with any games database that allows you to select for positions where the King dominates a Knight placed in any corner.

The position in the lower right corner is the base case. The Knight has no safe flight squares and, presuming no other factors were present in the position, the White King would simply continue to g2 and h1, collecting the stranded caballero.
The position in the lower left corner exhibits a case where the King is controlling the c2 and b3 flight squares, while the Rook is preparing to collect the Knight on a1. This is very common in games, usually after Black has captured a Rook on a1.
The position in the upper left corner shows an example where the Bishop on a5 protects the c7 square, providing protection from His Majesty on c6 if the Knight finds conditions permit Nc7.
The position in the upper right corner finds the King lurking in the vicinity of the Knight, while the Bishop on e8 is dominating the Knight on h8. The Black King could consider approaching via either f6 or f8 before taking the final two steps to deliver the h8 Knight to the eternal realm. Of course, all these positions ignore other pieces on the board. But this diagram serves the purpose of presenting several typical positions where the King is prepared to dominate and perhaps even execute the wayward equestrian.

So, how does one trap a Knight with a mere King? It's a puzzle.

Puzzle-Mania Time
Macieja, Bartlomiej (2599) vs. Garcia Guerrero, Isaac Antonio (2295) #1 of 2
Black just played 36...Nxf2 equalizing material. What is the best path forward for White?

Lessons learned:
1. Yes, the Bishop can sometimes pair nicely with a King to dominate a Knight and force it to the edge. That's a loftier goal than simply taking advantage of a Knight already perched perilously on the rim.
2. Sometimes a King has to go backward to move the game forward. In general, our mental conditioning predisposes us to always advance. But there are exceptions in all phases of the game.

Macieja, Bartlomiej (2599) vs. Garcia Guerrero, Isaac Antonio (2295) #2 of 2
Black just played 38...f5, a very reasonable thought. How should White proceed?

Lesson learned: Sometimes chess is quite easy! Particularly when you just solved an earlier puzzle from the same stem game.

Korneev, Oleg (2580) vs. Gevorgyan, Irina (2311)
Black just played 21...Nb3+, looking to grab an Exchange as some level of compensation for White's dangerous passed pawn on c6. How should White proceed?

Lesson learned: There is quite often no need to immediately grab the dis-armored (no, that's not a real word) horseflesh snorting in the corner. As long as all the exits are covered there is time for other adventures on the battlefield.

Danin, Alexandre (2590) vs. Bingert, Tim Niklas (2198) #1

Black initiated a short combination and just played 13...Nc2+. Obviously Black will capture on a1, so we need to decide now how best to trap the Knight once it reaches a1. Does it matter that the Bishop on c4 already controls the b3 square?

Lessons learned:
1. Timeliness is important.
2. And the Bishop on c4 is absolutely critical as play might continue 15...Rb8 16.Be3 Best. And now we see that without White's light-squared Bishop the Knight could escape via b3 thanks to the Rook on b8.

Danin, Alexandre (2590) vs. Bingert, Tim Niklas (2198) #2
In the following position we examine what happens if White responded to 13...Nc2+ with 14.Ke2 Nxa1 15.Kd2. How should Black continue?

Lesson learned:
1. After 13...Nc2+ White needed to play 14.Kd2 and take the most direct path with His Majesty to the c3 square in order to add protection to the b3 square. 14.Ke2? would have been an error. Sometimes the direct path is the truest path, Robert Frost's The Road not Taken aside.
2. Trickery in the absence of purpose is just a flawed magical trick waiting to go awry. Bottom line: If a piece is trapped in the corner, make sure it stays trapped. Or that you get something equally or more valuable in return for allowing it to escape.

Danin, Alexandre (2590) vs. Bingert, Tim Niklas (2198) #3
Turning to a point earlier in the game, Black just played 10...Qe6. The idea, apparently, was to continue with 11...Qg6 and the Knight fork threatened on c2 is quite annoying. How should White respond?

Lessons learned:
1. Recognizing that a piece, in this case the Knight on b4, has zero flight squares should trigger efforts to find a way to close the jaws of a trap on that piece. Or, if you own that piece, you should be looking for ways to find an exit or offer sufficient protection.
2. Recognizing that Black's move 10...Qe6 actually has evil intent, i.e., 11...Qg6 and 12...Nc2+, can save you a lot of pain.
3. Being able to calculate five moves deep (moves 11 through 15) is a necessary skill as you improve.

How can a piece that moves so obscurely ever be trapped? It must be the short legs. And bad corners.

Moiseenko, Alexander (2678) vs. Hernandez Carmenates, Holden (2580)
Are Knights trapped in the corner always bad? Stupendous question!! But what does that question have to do with this position? Black just played 30...Kc8 and White's Rook looks entirely out of sorts. How should White proceed?

Lessons learned:
1.Sometimes self-entrapment is the noblest gesture! White won by realizing they needed to lodge their Knight in the corner.
2. Even strong grandmasters can misevaluate the King and Pawn endgames that result after all the pieces are exchanged. I am absolutely certain Black must have seen White's combination. But only a misevaluation of the resulting ending would have led Black to play 30...Kc8??

Grachev, Boris V (2670) vs. Chekhov, Sergey (2470)
Black was in trouble. Down a pawn and with a Rook that could only shuttle, with difficulty, between b2, c2 and c3. Then Black spotted a desperate sacrifice and played 31...Rc3+. Can you find the best moves?

Lessons learned AFTER reviewing the rest of the game (shown below)!
1. Black had an interesting idea.
2. Black's damaged pawn structure and no clear targets on White's side of the board meant that the odds of Black's sacrifice working were minimal.

Kempinski, Robert (2597) vs. Movsesian, Sergei (2721)
White just played 36.Ng5, a challenging move to face given the threat of 37.Nxe6+. Can you find the best sequence of moves? DIFFICULT!!

Lessons learned, hopefully minus too much anguish.
1. Chess at the highest levels is hard. Calculations require steely efforts to peer through the mists and find concrete moves.
2. We were reminded that the King needs to be used as an offensive piece even in the endgame. Keeping that Knight under lock and key by controlling the g5 flight square was absolutely crucial.
3. As seen previously, sometimes the point of trapping a piece is simply to hold it in place long enough to secure winning advantages elsewhere on the board!!!
4. White loses so much time and material extracting his Knight that his game is hapless indeed.

What shall I do with you now, my puppet?

Secrets of Trapping Pieces: Knight Trapped by King + Piece

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