World team chess tactic

9 comments

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  Medhat says:

  July 17, 2011 at 10:37 pm

  1… Rc8 ! wins

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  Yancey Ward says:

  July 18, 2011 at 12:45 am

  This one was not easy to see, though I had the right idea almost from the start, just the wrong first move. I spent a while trying to make 1. …Na3 work, but it is one move too slow as white can protect c2 with the first rank rook on the third move. After about 15 minutes, it finally occurred to me to actually look at using Rc8 as the first move rather than the second for black, and this proved fruitful:

  1. …..Rc8!

  White has a number of replies here, but I will go through them one by one.

  2. ef6? Na3
  3. Kb2 Rc2
  4. Ka1 Nc4
  5. Nc1

  There are checks white can use, and I did look at them in a cursory manner, but none look like they give true counterplay as the black king can reach d8 and be completely safe with the knight guarding d6. 5.Nc1 is the only way to protect a2, but it isn’t enough since b2 is vulnerable, too:

  5. …..Qa3 and nothing can prevent Qb2#, only delay it.

  Or:

  1. …..Rc8
  2. Rc4 Qc4!
  3. Nfd4

  Here, 3.Rd2 is met by Ne4 as is 3.Ne1. Continuing:

  3. …..Ne4

  Hard to say what the best move here is for black- I think either de5 or Ne4 are playable, but on de5, things seem messier to me if white plays a move like Qg7- I think the line should favor black, but it is not completely clear to me: [3. …de5 4.Qg7 ed4 5.Nd4 (or 5.Rd2 d3 6.Qh3 Ke7-+) 5. …Nd5 6.Re1 Kd8! 7.Qh8 Kd7 8.Qe5 and so forth. You tell me this line is good enough for black? I simply can’t be sure]. Continuing:

  4. Re1 d5 and black is up the exchange with a potent attack.

  Or

  1. …..Rc8
  2. R1d2

  The move that foiled my initial plan of 1. …Na3, but it is now too late:

  2. …..Nd2
  3. Qd2 de5
  4. Ne5 O-O
  5. Kb2 Qb5 and black has won the exchange again.

  Or

  1. …..Rc8
  2. Nc5 Na3
  3. Kb2 dc5! and black has won an entire piece.

  Or, the most interesting line to me

  1. …..Rc8
  2. Rd6 Ne4!! (threatens Nc3#)
  3. Rd8 Rd8
  4. Rd8 Kd8
  5. Qh4 Kc8
  6. Qe4 Rd8 and black is again up the exchange, but with a less safe king himself, but the initiative for black is quite powerful, and white will have to block up the d-file with one of the knights.

  Fascinating position, though. I did confirm the correctness of Rc8, or at the very least, this is the move that Shoker actually played, though Areshchenko chose to defend with the worst of the moves above.

• Reply

  

  Venky [ India - Chennai ] says:

  July 18, 2011 at 12:22 pm

  Hi Susan Polgar,

  Well this throws up few possibilities – Nice puzzle.

  Black wins the game.[ Variations exist ]

  Example
  =======
  1. .. Rc8
  2.e*Nf6 Na3+
  3.K*b2 Rc2+
  4.Ka1 Nc4
  5.Re1+ Kd8
  6.R*d6+ N*Rd6
  7.Nc1 b3
  8.Nd4 Ra2+
  9.Kb1 Ra1+
  10.Kb2 Qa3+
  11.Kc3 Qc5+
  12.Kd2 Q*Nd4
  13.Ke2 Re8+
  14.Kf3 R*Re1
  15.N*b3 Qe4+
  16.Kg3 Nf5+
  17.Kh2 Rh1++ Mate

  White wins the game

  By
  Venky [ India – Chennai ]

• Reply

  

  Ravi says:

  July 18, 2011 at 12:27 pm

  1. Nd5 (threatening Nc3#), Rxd5 (not taking the Knight makes it worse through Nc3, Rxc3,bxc3)
  2. Na3+, Kxb2
  3. Nc4+, Ka1 (Kb1 and Kc1 lose to Qa3)
  4. Qa3 (threatening Qb2#), Rb1
  5. Rc8, Ne1 (supporting the c2 square)
  6. Rc6 (threatening Ra6), Rxd6
  7. Nxd6, exd6
  8. Ra6, Qe3+
  9. Kf8, Qe7+
  10. Kg7 and White cannot prevent the mate at a2

• Reply

  

  Dragan says:

  July 18, 2011 at 1:29 pm

  too easy…
  (just kidding!)
  may be: 1. Rc8

• Reply

  

  Yancey Ward says:

  July 18, 2011 at 4:50 pm

  Ravi,

  At first, I thought you might have it- I never considered Nd5 yesterday as the first move, but then I noticed that in the key line, white does have a way to guard a2 and the c3 square when the knight moves to c1 to protect a2:

  1. …..Nd5
  2. Rd5 Na3
  3. Kb2 Nc4
  4. Ka1

  Here, 4.Kc1 is mate in two after Qa3+, but I think 4.Kb1 is going to be ok, too, for white, though I didn’t look more than a move or two ahead in that one. Continuing:

  4. …..Qa3
  5. Rb1 Rc8
  6. Ne1

  There is no need to support the c2 pawn at the moment, black’s knight is in the way of the rook, but I will follow your line. In this position, white probably does better with a move like Qg7 followed by ed6. Continuing:

  6. …..Rc6

  This was the move in your line that excited me, but it is too slow:

  7. Qg7 Rf8

  There is no time for Ra6: [7. …Ra6 8.Qh8 Kd7 (or 8. …Ke7 9.ed6 Ke6 (or 9. …Kd7 10.Nc5+-) 10.Nc5+-) 9.Nc5 Ke7 (or 9. …Kc6 10.Qa8 with mate to follow) 10.ed6 Rd6 11.Rd6 and white will be up a rook with firm control of the c3 square.] Continuing:

  8. ed6 Ra6
  9. Nc1 and a2 is well guarded. I don’t see any mate now.

  In any case, that was a nice try. Definitely out of the box thinking about how to get at white’s king.

• Reply

  

  Ravi says:

  July 19, 2011 at 6:00 am

  Yancey on your comment. After the Nc1 can’t Black still win with Qc3+?

• Reply

  

  Ravi says:

  July 19, 2011 at 9:01 am

  Sorry, I overlooked the ed6. That clears the c3 threat.

• Reply

  

  Venky [ India - Chennai ] says:

  July 19, 2011 at 10:44 am

  Hi Susan Polgar,

  In my previous post – after giving the winning set of moves for Black – Wrongly typed as,” White wins the game” – just because I had turned tired playing against myself [ playing for both color pieces on my manual chess board ] and changed my moves often,to make the final set of moves interesting.

  As I said in that post – variations exist but win for Black assured in this puzzle,if played wisely.

  Thoughtful alternative set of moves given by Ravi – Nice.

  By
  Venky [ India – Chennai ]