World Solving Championship solutions (1)

by John Nunn
9/24/2017 – This Problem Solving event took place in Dresden, Germany, in early August. We reported extensively on it and gave you eight problems from the Championship to solve. Not an easy task, as most of them required some experience in this entertaining and challenging field. Today we give you the solutions of the first four problems, wonderfully annotated by top problem solver Dr John Nunn. The remaining four solutions will follow later this week. Learn and enjoy! | Photo: Franziska Iseli

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Solutions, Dresden, 2017 — Part 1

By John Nunn

The 41st World Chess Solving Championship took place during the second week in August in Dresden, the capital of the German state of Saxony. The solving event has been running since 1977 and is a well-established part of the annual World Congress of Chess Competition. Recently it has been utterly dominated by Poland, who have won every year since 2009. We reported on this year’s event two weeks ago. Today we bring you the solutions to the first four problems given there.

The Championship began with an Open event, which was won by Piotr Murdzia; I came second and Vladimir Podinic third. The image at the top of this report shows the winners (Nunn, Murdzia, Podinic). Here is an attractive study from the Open event.

[Event "The Problemist"] [Site "?"] [Date "2011.08.22"] [Round "?"] [White "Timman, J."] [Black "White to play and win"] [Result "*"] [Annotator "Nunn,John"] [SetUp "1"] [FEN "6b1/6kp/3R2P1/8/p2K3P/p7/P7/8 w - - 0 1"] [PlyCount "15"] [EventDate "2011.??.??"] {Sometimes the main difficulty in solving a study isn't finding White's moves, it's finding Black's defence. For a long time I couldn't understand why 1 h5 didn't win comfortably, until I found Black's first move.} 1. h5 ({Nothing else looks promising; for example,} 1. gxh7 $2 Bxa2 2. Ra6 Bb3 3. Ra7+ Kh8 4. Kc3 a2 5. Kb2 Be6 6. Rxa4 Kxh7 {and the advanced Black pawn prevents White from winning}) (1. Ra6 $2 Bxa2 2. Rxa4 Kxg6 3. Rxa3 Be6 4. Ke5 Bc4 {is a theoretical draw since Black plays ...h6 and White cannot make progress.}) 1... Kh6 {At first I thought White was winning easily, since} (1... Bxa2 2. Rd7+ Kg8 3. Rxh7 Be6 4. Kc3) (1... hxg6 2. Rxg6+ Kh7 3. Rxg8 {are both simple wins. Then I realised that playing the king to h6 created problems for White.}) 2. Rd8 (2. g7+ Kxg7 3. h6+ Kh8 4. Ra6 Bxa2 5. Rxa4 Bb3 6. Rxa3 Bf7 {also leads to a position in which White cannot make progress, since any winning attempt just leads to stalemate.}) 2... Bxa2 3. Rh8 Bg8 $1 {A spectacular idea, and much more troublesome than} (3... Kxh5 4. g7 Bf7 5. g8=Q Bxg8 6. Rxg8 {when White wins easily after, for example,} Kh4 7. Rg2 h5 8. Ke3 Kh3 9. Kf3) 4. Kc3 $1 { Some solvers remarked afterwards that your natural inclination is to advance the king and not retreat it to a1, which made this move hard to see. The formation in the top right corner is in a state of paralysis, so for a few moves the action is limited to the king and a-pawns.} a2 5. Kb2 a3+ 6. Ka1 { But now White is really threatening to take the bishop, so Black is obliged to defend it.} Kg7 7. h6+ $1 {An elegant finish.} Kxh8 8. g7# *

The next day we were on to the serious business, the World Championship itself, which lasts a total of two days, with three rounds each day. The very first round consists of three mates in two, which have to be solved in 20 minutes. Although Axel Steinbrink, who set the problems, chose a rather sneaky one to start with, the leading solvers coped with this and all scored 100%. Here is the most attractive of the three.

[Event "1st Pr Sydney Morning Herald"] [Site "?"] [Date "1905.08.22"] [Round "?"] [White "Mackenzie, A."] [Black "Mate in two"] [Result "*"] [Annotator "Nunn,John"] [SetUp "1"] [FEN "3nbb2/Q1pr1pp1/B7/p1PP3p/K1Nk3r/1RN1RPP1/8/B7 w - - 0 1"] [PlyCount "3"] [EventDate "1905.??.??"] {Sometimes an experienced solver can spot enough clues in the diagram to find the solution very quickly. This one only took me two minutes to solve, which was just as well as I needed the time to solve another problem in the same round which I found quite tough. The first thing to note is that Black can give a discovered check by moving the d7-rook. After 1...Rd6+ or 1...Re7+ the path of the bishop from f8 to c5 is blocked and White can reply 2 c6#. However, after 1...Rxd5+ there is no mate because the obvious reply 2 Nb5+ (using the fact that the rook blocks d5) fails because of 2...Kxc4. So it looks as though the key move must allow White to meet 1...Rxd5+ by 2 Nb5#. The obvious idea is to move the c4-knight away so that c4 remains covered even after Nb5. However, the knight move must create a threat and, given that the black king can now move to e3, this can only be Nc2# or Nf5#. So the key must be either 1 Na3 (threat 2 Nc2#) or 1 Nd6 (threat 2 Nf5#). However, the latter is refuted by many moves, for example 1...cxd6. So the key is} 1. Na3 {which surprisingly allows Black to take the e3-rook with check. But there's a nice mate prepared after} Kxe3+ (1... Rd6+ {or 1...Re7+} 2. c6#) (1... Rxd5+ 2. Ncb5# {and}) (1... Rh2 2. Re4#) 2. Ne4# {and the other variations are} *

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The second round of mates in three proved more troublesome, and a number of solvers, myself included, dropped points through missing variations. In problem-solving events you have to give complete solutions, including all variations, in order to score full marks on a problem. It’s quite easy to overlook a relatively minor line and drop a point or two. The following problem from this round should appeal to over-the-board players.

[Event "1st Pr Cesky spolek sachovni v Praze"] [Site "?"] [Date "1891.08.22"] [Round "?"] [White "Hlineny, J."] [Black "Mate in three"] [Result "*"] [Annotator "Nunn,John"] [SetUp "1"] [FEN "3N2Q1/3pN2p/7p/2p1k1p1/R5p1/6P1/P4K2/8 w - - 0 1"] [PlyCount "5"] [EventDate "1891.??.??"] {Once again, clues in the diagram can greatly shorten the solving process. The outlying pawn on a2 provides a strong clue that the black king will move within range of the pawn during the solution. Since at the moment this is impossible, it seems very likely that the key move will allow the enemy king to move to either d4 or d5. However, since two white pieces are covering d5, only d4 can be freed in one move. This immediately suggests either the sacrificial 1 Rd4, or a move of the rook along the a-file. After1 Rd4 Kxd4 there is no mate, so the main problem is to determine which square on the a-file the rook must move to. At first sight the most likely move is 1 Ra6, which at least arranges the mate 1...Kd4 2 Rd6+ Kc3 (2...Ke5 3 Qd5#) 3 Qb3#. However, this move, which takes away the squares d6 and f6 from the black king, looks too obviously strong to be the solution, since problemists tend to favour unexpected moves. Indeed, a check shows that 1 Ra6 is met by 1...d6! and there is no mate. So if it isn't a6, which square is it? To determine this, it's simplest to imagine Black has played 1...Kd6 and work out where the rook has to be for a mate in two. If the king can flee to c7 then there is no mate, so} 1. Ra7 {is the next most likely candidate. If you then spot that} Kd4 (1... Kd6 {can be met by the spectacular} 2. Qe6+ $1 dxe6 3. Nf7# {that is confirmation that 1 Ra7 is indeed the correct move.}) (1... -- 2. Rxd7 { is a threat, meeting} Kf6 {by} (2... -- {or else} 3. Qe6#) 3. Qh8# {The other variations are}) (1... d5 2. Nec6+ Ke4 (2... Kd6 3. Qe6#) (2... Kf6 3. Qe6#) 3. Qxh7#) (1... d6 2. Ke3 {threat 3 Qe6#} Kf6 3. Qh8#) (1... Kf6 2. Rxd7 {mates by 3 Qh8# or 3 Qe6#}) 2. Rxd7+ Kc3 (2... Ke5 3. Qe6#) 3. Qb3# *

The third round of endgame studies generally causes quite a few problems, especially for problemists who are not always strong over-the-board players. At one time I could count on gaining a lot of ground in the study round, but these days most of the leading solvers are also good OTB players (there were several over-the-board IMs and GMs competing at Dresden) so this advantage has more or less disappeared. Here’s an endgame study from this round which features a common over-the-board tactical idea, but in a very unusual setting.

[Event "Original for WCSC"] [Site "?"] [Date "2017.08.22"] [Round "?"] [White "Sobrecases, G."] [Black "White to play and win"] [Result "*"] [Annotator "Nunn,John"] [SetUp "1"] [FEN "6K1/4p2B/P1P5/7k/2n5/r5B1/4r3/1R6 w - - 0 1"] [PlyCount "31"] [EventDate "2017.??.??"] {Curiously enough, some engines have a bit of trouble with this position, going to considerable depth without giving a clear win. Komodo, however, finds the key idea relatively quickly. It's not so easy for humans to solve either, although most of the top solvers managed it. At any rate, White cannot afford to let his g3-bishop fall with check.} 1. Bg6+ $1 {is the spectacular start to the study, offering a piece simply to block the g-file.} ({The more obvious} 1. Rh1+ Kg4 2. c7 Nb6 3. Rb1 Nc8 4. Rb8 Rxg3 5. Rxc8 Ra2 {isn't energetic enough and only leads to an ending with R+B vs R.}) 1... Kxg6 2. c7 Nd6 (2... Rxg3 3. c8=Q Kh6+ 4. Kh8 Rh2 {may look troublesome, but White wins easily enough by, for example,} 5. Rh1 Rxh1 6. Qc6+) 3. Bxd6 Rc3 4. a7 Ra2 {The first key position. Black has managed to place his rooks behind the two dangerous pawns and it seems unlikely that White can achieve more than R+B vs R. However, by exploiting an unusual tactical possibility White can disrupt Black's defence.} 5. Ba3 {The first step is to the draw the enemy rooks onto the same rank with this bishop sacrifice.} Raxa3 6. Rb6+ {A preliminary check is necessary or White will be mated on the back rank.} Kf5 (6... e6 7. Rxe6+ Kg5 8. Re3 $1 { is a deadly skewer. White wins after} Rxe3 9. c8=Q Rxa7 10. Qc5+ Kg6 11. Qb6+ { followed by the capture of either rook.}) (6... Kg5 7. Rb3 Rcxb3 8. c8=Q Rxa7 9. Qc5+ {also wins as the Q vs R+P position is hopeless}) 7. Rb3 $1 {Two rooks forked by any enemy rook in between is an unusual sight on the chessboard.} Rxc7 (7... Raxb3 8. a8=Q Rxc7 9. Qd5+ Kg6 10. Qe6+ {is also hopeless}) 8. Rxa3 Rc8+ 9. Kf7 e5 10. a8=Q Rxa8 11. Rxa8 {is a won R vs P position, for example} e4 12. Re8 Kf4 13. Ke6 e3 14. Kd5 Kf3 15. Kd4 e2 16. Kd3 {rounds up the pawn.} *

Full solutions to the remaining four problems with explanations will be provided by the author in a separate article, shortly.

You can also download a PGN of the selected problems without solutions but with pointers by John Nunn to help you solve them, e.g. with ChessBase or a Fritz-compatible program.

Portisch book

John Nunn is a director of Gambit Publications, a leading chess book publisher. They have some interesting new books out this year.

In his day, Lajos Portisch was known for his meticulous opening preparation and in this book he opens his files and shows how key ideas in the Ruy Lopez have evolved from the 1960s to the current era. See for more information.

Afek book

Yochanan Afek, a Grandmaster of Composition and an over-the-board International Master, explores the world of extreme chess tactics, using a host of entertaining examples from over-the-board play and the world of endgame studies. See this page for more information.

These two Gambit books are available in print, Kindle and app form. Using the app, which is available for iOS and Android devices, you can play over all the moves on-screen.

Gambit publications

Dr John Nunn (born 1955) is an English grandmaster, author and problem-solver. He was among the world’s leading grandmasters for nearly twenty years, winning four gold medals in chess Olympiads, and is a much-acclaimed writer whose works have won ‘Book of the Year’ awards in several countries. In 2004, 2007 and 2010, Nunn was crowned World Chess Solving Champion. He continues to compete successfully in over-the-board and problem-solving events.


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