Slump - Sipma
Wouter Sipma (r.) thinks about how to respond to Jitse Slump's opening move 31-26.
Photograph: G. van Dijk

Slump - Sipma

To applet

Trying to win from dangerous position becomes fatal to black player

Author: Wouter Sipma
06-02-2024

It is an honour for me to write an article for Damkunst! Some wonderful analyses have already been written (and hopefully read!). May many more follow.

My 'task' was to analyse a game from the 2023 Dutch Championship (in Drachten, December 2023). The choice was plenty: a strategic masterpiece by champion Groenendijk (in fact, all his victories), a fight game by Baliakin (especially his encounter with super-talent Boxum was epic - a fascinating game type and more than 70 moves of tension) or something of my own? Almost all my games were interesting, with a few experiments here and there that turned out to be good or bad... In the end, in consultation with the chief editor, the choice fell on my game against Jitse Slump from the twelfth round. This because of the rare character of the game after the opening and the fact that I can tell it from the first-person point of view as well as an 'all-knowing analyser'.

I played my last game against Slump 36 days earlier, almost 9,000 km away in the seventh round of the World Cup in Lishui, China. In that game, Slump saddled me with discomfort on two wings as early as the opening, which meant I was relegated to a mere spectator in the middle game, who had to see how I would fare (I survived). Now I had resolved to be well prepared for the game and had thought of an answer to all the opening moves. Except…

1.31-26...This move was unexpected (and with good reason, Slump had only played this move twice before, against Mezhenin in 2018 and Van IJzendoorn in 2019, without sensational success) and I sunk into some pondering. In China, Van IJzendoorn also confronted me with 1. 31-26 – what would Slump have thought?
After a while, I decided to go for a variant I had wanted to put on the board six rounds earlier against Jan van der Star, but with white.

1....18-232.36-3112-183.41-367-124.46-412-7Van der Star chose 4...1-7 here. 5.31-2720-24And Van IJzendoorn continued here with 5...20-25 in the aforementioned game against Slump. The game move is an "invitation that white cannot actually refuse" – in Slump's words in the demonstration room after the game.
6.34-29!?23x347.40x2015x248.27-21!16x279.32x21...
This way of playing has been familiar to me for a long time - I must have been about 18 years old when I had my first experience with it in a training setting with (a much younger) Groenendijk and Van IJzendoorn. Slump was not there yet but has more than caught up with this (knowledge) gap.
In my database, I see that this position has occurred 31 times, but the number of practical examples in which white actually tries to play a constructive strategy can be counted on one hand. Funny: the first time I count for this is the Sharafow-Zalitis game, semi-final of the 1967 USSR championship in Nizhny Tagil – but with build-up from 47 instead of from 46! For me, however, the prime example is Sijbrands-Van den Hurk (NC 2001); in terms of similarities to Slump-Sipma, however, the relatively recent Van IJzendoorn-Pan (World Championship 2019), is much more important! This game, which ended in a draw after a fierce fight, will be referred several times below.
Piquant detail: since 2015, I have been to every World Championship (whether I managed to qualify for the final is a second), except for the 2019 World Championship – for Slump, this was precisely his first World Championship final, and therefore he was able to watch Van IJzendoorn-Pan up close. After reading this article, you may decide whether this did not help him, at least subconsciously...

9....19-239...18-23 and 9...10-15 are also played. It does not seem to me that white must fear the exchange with 12-18, after which black's position is somewhat unbalanced. 10.33-29!23x3411.39x1914x23
11...13x24 is also possible, but is toothless – after a development with 18-23, 12-18 white's structure remains nicer and if black does want to develop from 5, it is better to do so immediately. The text move is therefore more principle.
This is a good time to reflect on the ideas of the opening and the objectives of both players.
The position revolves around binding on black's short wing: because of the open square 2, black cannot play here, the white pieces on 21 and 26 (supported by 36 and 37) hold the black 'lego block' 1-6-7-11-12-17 – very economically. Because white was able to remove the piece on 33 with the previous exchange, the position lends itself perfectly to a lock-up strategy: after all, black can now only force 21-16 with a concession (18-22).
With these determinations, the goals for both colours can be determined:
- white wants to maintain the economic lock-up;
- white will continue to avoid square 33 for this purpose;
- white also wants to gain control on the right wing (square 30);
- white will try to play to the right as much as possible;
- white will try to exchange pieces to make the lock-up more pronounced;
- black wants to develop pieces from the lock-up;
- black will build a strong center and push white to the edge;
- black will want to attack from a strong center (sixth row);
- black will try to keep the pieces on the board.

Whereas in a battle between attack and surrounding the surrounding player often has the most difficult task, I think that in this case it is precisely black who is most at risk. The piece on 1 still has a function (prevents combinations to square 1), but piece 6 is really offside. Furthermore, it is often good for an attacker/center player to break open the position, but that doesn't apply here either: even if piece 21 is moved to 16, it still keeps five pieces (1-6-7-11-17) occupied. If piece 6 is on the other side of the board, I think it is precisely white again who is more at risk.
I was aware of the risks (especially against a formidable opponent), but to get on the podium something special had to happen, knowing that Baliakin awaited me in the final round. Moreover, the same was more or less true for Slump, although he faced Boxum in the last round. So we were both happy with battle on the board. 12.36-31...Van IJzendoorn played 12.37-31But that exchange is not as innocent as it seems: Pan could have sabotaged the development of the white long wing with 12....13-19After 13.41-37then follows 13....17-22!and black is free. However, Pan played 12...10-14 (and Van IJzendoorn quickly 13.41-37), keeping the sides in each other's way.
12....10-1413.45-4014-19A more non-binding configuration with 5-10, 14-20, 10-14 and so on was also an option to keep the development with 13-19 in the position. However, chances are that this would only have led to move change with the game variant. With 13... 14-19, black takes the opportunity to 14. 41-36(?) (or also 14. 43-39(?)) to 'punish' with 17-22(!) − but white can do just fine without these moves. However, 13... 14-19 has another advantage, which I will come back to in the next move. 14.35-30...
14....5-10It could be that 14. 35-30 is slightly inaccurate. I knew that in his game Sijbrands immediately 'closed' white's left wing with 13. 41-36 and 14. 37-32, but didn't see how I could take advantage of leaving these moves out for the time being. The computer programme Scan did propose an idea: 14...18-22!?15.21-16*22-27!?16.31x2217x28
By exchanging the white piece on 31 with it, black clears the way for developing piece 6. However, it is not certain that this will work: under the current circumstances 11-17 is prohibited. Black can move a piece to square 20 to remove the threat, but in the meantime white plays e.g. piece 37 to 27 to interfere again. Therefore, it seems smart to play 17.37-3112-18!18.44-3918.40-34is an option to keep hindering 11-17 for longer, but white has thereby lost flexibility on his short wing. 18...11-17Now that the piece on 6 is 'liberated', so to speak, black has a much better starting position for the middle game: although white should still have play against the black center attack, the difficulty is a lot higher than in the game!
It could be that in this variant, white has better to consider a plan like 17. 38-32 and then move piece 41 to 27, to keep the position more closed. But even then black manages to continue 11-17.
The intelligent reader will wonder if black could then not have played 18-22 immediately after 12. 36-31 (13. 21-16 22-27x28). In that case, however, white is one move faster to attack piece 28 via square 33, so not entirely "free". By the way, it is always amusing to see how the two leading analysis programs of the moment −Kingsrow and Scan− differ on the value of the position. The programs each have their own preferences and traits: Scan prefers attacking positions and tempo advantage (which sometimes leads to banal −but not weak− opening play) and often gives relatively high ratings in all kinds of positions, while Kingsrow cares little about tempo relationships and in terms of value is not so quick to get excited. Where Flits used to be my only 'digital sparring partner', it is now possible in the latest versions of the unsurpassed Turbo Dambase to switch on several engines simultaneously. This way, you are sitting at the table with two super strong draught players at any given moment, so to speak! Needless to say, my Flits is now retired... 15.40-359-1416.44-3914-2017.37-32...After two more moves in which black has rejected the 18-22-27 option, white now finally closes the tent. 17....10-1418.41-364-919.49-44...
The preliminary deliberations are over, and the players have taken their positions. Now it is time to make choices. If we play 19.42-37 here and put piece 14 on 15, we have the position between Van IJzendoorn and Pan! Also, Sijbrands-Van den Hurk is not much different (move 30 on 40, 50 on 45 and 20 back on 15) − at that moment, however, Sijbrands played 18.21-16, releasing his opponent. I don't see what is against keeping the lock-up with 18. 35-30 (18.... 18-22 19. 21-16 14-20 20. 40-35(!)). In the Volkskrant article of February 24, 2001, this Sijbrands mentions this game ("about which more later this year"), but I cannot find myself when he returned to this. If anyone does know this, I would be happy to see it − and if not, we still have an analysis to look forward to! Anyway, I prefer the construction of Slump, who with 19. 49-44 deliberately leaves piece 50. Piece 50 will also play an important role in the game. 19....20-25Before going into the clash, I was eager to put another weakening on white − white does not have a free tempo. 20.42-3725x3421.39x3014-20And so, after a short detour, we ended up right back in Van IJzendoorn-Pan! 22.47-42...
Van IJzendoorn chose to go after 22.43-3918-2223.21-1612-1824.44-409-14and move his crown piece with 25.48-42− more on that later. 22....18-22En garde!
Attacking again with 22...20-2523.44-3925x3424.39x30did not seem logical to me because, again, one pair of the pieces disappears and piece 50 can then be played to the center. Interestingly, Kingsrow now recommends 24....23-29!?followed by 19-24 − of course, there may be something in that now that white is playing without 47 and 49. 23.21-16...Of course, white does not allow the exchange with 12-18. The lock-up is transformed because now piece 16 will occupy the square 1-6-7-11 − at least, as long as 6 and 11 cannot get out. 23....22-28Played to get ahead of the capture of the fork-lock with 32-27. The intention for black now is to strengthen the center and −keep holding the dream− develop piece 6. 24.44-39...
24....20-24With the text move, black is heading for a frontal clash. With 24...19-2425.30x1913x24black could still avoid, but I didn't see how to continue after 26.39-349-1327.43-39; in the position after 27....23-2928.32x2329x18in any case, black has little to expect. The lego block is still there. 25.39-34...White looks for the right attacking angle and keeps waiting − see here the usefulness of piece 50: now and the next moves, white can exchange forward with 50-45x34 after 24-29. After a premature 25.31-27black is in no particular danger after 25....17-2126.26x1711x3127.36x27Besides defending 28 with 6-11 or 24-29, the engines also point to a third (combinative) option: 27....12-18!?28.38-33
(otherwise, black gets time for 7-11x12) 28....8-12!29.33x227-1130.16x723-28!!31.32x149x2032.30x171x4133.22x1341-46and if black pays close attention to his king, it becomes a draw. 25....9-1426.43-3912-1827.50-45...
And so, via move changes, we end up back at Van IJzendoorn-Pan, the only difference being that piece 47 is on 48! 27....8-12In the game, I spent quite a bit of thinking time on 27...17-22A)but did not see a good combination after 28.38-33?However, there is one: 28...7-12!29.16x76-11!(29...23-29 or 29...24-29 followed by 30... 22-27, 31... 23-29 is too expensive) 30.7x1623-29!31.34x23After 31.32x2329x4732.45-40follows the same reaction 31...18x4732.32x2319x2833.30x1022-27!34.31x3347x4B)During analysis, Slump −in chorus with Van IJzendoorn, who was only too happy to stand at our board in connection with his own failed game to reminisce− gave a much stronger answer: 28.26-21B1)8-12B1a)29.32-27
B1a1)With this wonderful configuration, white manages to restrain the black wing for a second time. 29...11-17is, after all, (permanently) prevented by 30.38-33!17x2631.27-21!26x1732.31-2722x3133.33x2+-B1a2)29...24-2930.48-43!29x4031.45x3414-2032.38-33!etc. by no means makes life easier for black. B1a3)29...14-2030.30-25!3-831.25x1419x1032.38-3332.48-43probably wins as well, but is less logical. 32...24-2933.33x2411-17and white can play with its prey: for example, capture the wing a third time 34.42-3817x2635.38-32... and let it escape again... 35....28-3336.39x1922-2837.32x2318x20to get there with 38.27-2213x2439.34-3024-2940.30-24
then put an end to it anyway. See how the pieces on 16 and 22 continue to control the wing for the fourth time! B1a4)29...3-8and the clearest may be 30.48-4324-2931.30-2529x4032.45x3419-2433.37-32!28x1734.34-3022x3135.30x10+-B1b)Of importance is that after 28...11-1729.21x128x1730.38-33the sacrifice 30....24-2931.33x2428-3332.39x2822x33is refuted by 33.48-43!33-3934.43-3839-4435.24-20!14x2536.34-29+-B1c)After 29.31-26?11-17!30.30-256-11!black does have what he wants. With the 6-11-17 formation out of commission, white comes into play: 28.31-27!17-22!
The logical consequence of black's previous move − other moves weaken my position. 28...14-2029.30-25!17-2230.25x1422x3131.36x2719x1032.38-33!12-1733.33x2217x28is perhaps still just playable for black, but requires the necessary arts and crafts after 34.26-21 or 34.48-43. 29.38-33...Slump chooses a clear variant with forced play. He could also have chosen to increase the tension even further with 29.36-31!?The spectators present, including Roel Boomstra, occupied themselves with this position for a while, but the players had both scarcely looked at it. It does pose a risk for white to play without piece 36, but the threat of forming a chain lock also limits black immensely. Let's look at a couple of variants. 11-17A)30.38-33?the most logical move to then advance 42-38 with winning chain lock. 30...23-29 is now too expensive, but black has another arrow on his bow: 30...24-29!31.33x2428-3332.39x2822x33and black wins back the sacrificed piece with great advantage. B)30.30-25B1)and now black has a choice: 24-30(30...6-11 can lead to the same variants after 31.38-33, but also gives white an additional option in 31.34-30!?). 31.35x2419x30hoping to pin 45 is dangerous because of 32.38-33Or also first 32. 48-43 and then 33. 38-33 − the threat is now 33.26-21!, 34.27-21, 35.31-27 and 33x2. 32....6-11*33.48-43(or first 33. 42-38) 33....30-3534.42-383-9
Now 35.33-29? 13-19! 36.38-33 9-13! 37.43-38 1-6! 38.27-21 14-20 and so on is bad for white and after 35.27-21, 35...23-29 can be done, but there is an interesting option: 35.34-30?!35x2436.45-40after which black must choose from a variety of endgames: 36....14-1937.40-34B1a)9-1438.34-2923x3439.32x2319x2840.39x1028x4841.10-4or B1b)37...24-2938.33x2419x3039.25-2030-35or 28-3340.39x830x4841.8-340.20-149x2041.34-2923x3442.39x3035x2443.32x2318x2944.27x9
In practice, this seems to me to be a difficult consideration for black: it is already difficult to value each endgame, and then you have to choose one of the three....
B2)30...14-2031.25x1419x1032.34-3024-29and black seems to have repelled the chain, but... 33.30-24!?29x2034.38-33
This beautiful sacrifice (which white can even extend with 34.26-21!? 17x26 35.38-33) seems to put black in trouble by double threat 39-34 and 26-21, 27-21 31-27. However, if black remains calm, he will see that one of those threats is not so bad: 34....20-2535.26-2117x2636.27-2126x1737.31-2722x3138.33x213-193-839.37x261-740.2x116x17should also be possible, despite the white piece on 16. 39.2x2425-3040.37x2630x19with an equivalent position. B3)3-8is probably the most aggressive attempt: 31.48-4331.34-3017-2132.26x1722x11makes more room in the 6-22 section. 24-29and now white must choose between 32.27-21x34, 32.34-30 or 32.35-30 and the game continues. C)Waiting even longer with 30.48-43gives black a chance: 30....14-20!?After 3-831.30-25we are again in variant B3. 31.38-33?
I know - a white player might have to be naive to run into this combination, but it is a very nice one! Necessary is 31.30-25but after 31....24-29!32.25x1419x10!the battle continues − at least white no longer manages to encircle black. 23-29!32.34x25after 32.32x25black also always comes to 41: 32....29x4733.30x817-21!!34.26x2847-1535.8x177-1136.16x71x41-+3-8!33.32x2318x4734.27x912-18!!35.30x1918-23!36.19x288-13!37.9x187-11!38.16x71x41!!and two kings far outweigh three pieces behind.

Conclusion: 29.36-31 sharpens the battle and certainly gives chances for white, but black can still maintain its foothold in any variation and sometimes (as in the last variant) hit back!

And what about that other game (with 48 on 47)? There Van IJzendoorn could also do 29.36–31, and in that case, that would really be a one-way game, in which black has to work hard not to lose. Maybe that game should be looked at again... Back to the game. 29....22x3130.36x2712-1731.33x2217x28
32.26-21!...A nice move to leave the black block! After 32.42-38black can "just" play 32....11-17!By the way, Van IJzendoorn also had a good option here in his game with 32.27-22(!) 18x38 33. 42x22 ( thanks to piece 47!) − however, he played 32.30-25, and his advantage vanished. You can replay analysis variants for that game on Toernooibase. 32....3-833.42-388-1234.38-33...
This position was what both players had in mind on move 28. 34....23-29!35.33x22...35.34x23??18x3836.32x2319x2837.30x1711x4238.48x37goes wrong for white. 35....29x4036.35x4424x35For one last time, we return to Van IJzendoorn-Pan and specifically to the analysis section in Toernooibase: there Pim Meurs indicates that white can play 37.37-31!?, with which white offers a poisoned piece. However, Slump plays another move and with that, we say goodbye for good. It's still interesting that the games shadow each other for 36 moves! 37.45-40...
The heavy middle game part (with this analysis work) is over, and the game enters a new phase. Many pieces may have disappeared from the board, but Black still cannot move the 1-6-7-11 block. I judged that black should be able to keep the position equal because of the center formations black can create.

Moreover, Slump's last move worked a bit like a red rag on a bull: isn't that wing without 45 weakened? I wanted to keep fighting on, even for more than one point. But the interesting battle so far had taken its toll, especially on the clock: I was playing with 7 minutes, Slump with 15 (for 37. 45-40). 37....18-23To allow 32-28 no more. 38.37-31!?...Slump takes full advantage of his time advantage and presents black with an interesting choice. Although at this point I can't really go wrong yet, I commit the first inaccuracy here, which is promptly followed by two errors. 38....12-1838...12-1739.21x127x1840.16x71x12was by far the most logical, but after 41.22-1712x2142.27x16black must still be careful not to run a piece to 17. With a little policy, that should work − black can also rattle on white's short wing. A little trickier is 38...11-17?!39.22x21-740.2x116x2841.16-11and now it is tempting to win a second piece with 41....28-3313-1842.11-623-29is probably wiser, but even then black is not safe. 42.39x2823x2143.11-6but I saw some problems here because the white king can occupy the strong line 47-15 in combination with the "clamp" 44-40-35. During analysis, two grandmasters confirmed this feeling by not finding a quick draw − or in other words, here you need thinking time, which I did not have.

I realized with the game move (38...12-18) that I was burning my ships behind me −equally saying goodbye to the block 1-7-11-12− but did not immediately see what could happen to me.

39.31-26!23-29?A big mistake, effectively deciding the game. It was not too late to come up with 39...19-24(threatens regrouping with 13-19) 40.32-2823x3241.27x3818x2742.21x32enforce. White stands after 42....11-17somewhat better, but the pieces on black's long wing are moving again, and in a normal course, this will be a draw. 40.21-17!...
With a steady hand, Slump dismantled the black position, which broke into two parts. And by now, I was running out of thinking time as well... 40....19-24?The last mistake. On the move before, I had seen too late that after 40...18-23the mini combination 41.17-12!7x1842.16x71x1243.32-2823x2144.26x818x2745.8-3+-follows. A heavy blow, because that also makes 17-12 an immediate threat. That black can survive with 40...14-20!may be called a miracle. 41.27-21!41.17-1211-1742.12x2517x3743.48-4237x4844.39-3448x3045.25x2313-18!46.23x127x18and by the finesse 18-22, 6-11, black achieves a draw. After 41.32-28?follows surprisingly 19-23!42.28x87-12!!43.16x712x3244.22x131x3And suddenly, white has to fight for his life. 18x3842.39-33(the best) 42....11x2243.33x15
43....22-2844.15-1028-3345.40-3445.10-438-4246.4x3942-47=− this trick is black's lifeline in this endgame.
It looks like white simply has a king-for-1, while the black front pieces go nowhere. But as is often the case with draughts, reality is unruly. 7-11!46.16x71x1247.21-17After 47.21-1613-1848.26-2119-2449.34-29black really worms his way to king with 49....35-4050.44x3533-3951.29x2039-44and Kingsrow really do claim it will be a draw. 12x2148.26x1719-24!49.10-524-2950.34x2335-4051.44x3533-3952.5-10
52....39-4339-44?53.10-1544-5054.15x4750x1155.47-15followed by 15-4+ 52...38-43?53.23-19!13x24a special sacrifice, to ensure that a capture position is finally established that white can use: 54.10-1524-3055.35x2443-4956.17-116x1757.48-4349x2058.15x44+-53.48x3938-4254.10-442-4855.4x1848x25and the remaining 4x2 endgame is a draw... I don't even begin to count how many single moves black has had to play so far to get here (and how many more black has to find). In short: the practical value of this variation is very small, and I consider 39...23-29? to be the decisive mistake. 41.17-12!13-19Because 41...18-2342.39-347x1843.16x71x1244.32-28!23x2145.26x1018x2746.34x23is totally over. I realized by now that I was in a pinch, but thought I still had a chance with the action from the game. However, it was exactly right for white. 42.12x3424-2943.34x2319x37
Black has broken through − or so it seems. Unfortunately, the piece on 37 really can't pass because of 22-17! 11x31 26x46. And those pieces 1-6-7-11 are also not so easy to sacrifice to make the breakthrough possible... 44.40-34!...Slump finishes it impeccably. 44.39-33?is a mistake: 14-19!45.33-297-12!46.16x1837-41and on the next move 41-47 and black can still fight. 44....14-1945.34-2919-2346.29x1837-4147.18-1341-4748.13-9...Black still got to king, but it solves nothing at all. The square 41 is still taboo, as is 29/24/20/15 (39-33+), which prevents the black king from getting out of the corner. A brilliant picture that still does justice to the setup of the game: the lock-up of the black short wing is still a fact! I therefore quit the game.

Slump thus delivered his best game of the tournament: a good opening choice, strong continuation and above all, an excellent tactical choice not to enter the chaos with 29.36-31!?, but to choose a variant in which white −with pressure on the clock− can make things difficult for black, and it showed. In a span of three meager moves, an almost equal position turned into a lost one!
I hope you enjoyed this analysis − it was fun to make. I look back on the game with mixed feelings: it is always wonderful to fight such a high-level battle, but of course I would have liked the outcome to be different. Next time I write for Damkunst, I will try to include a win!

PS Would you like to read more about this opening and this game type? Then I have to disappoint you at first: I am not familiar with much material. Except for a game you have to know about: Boomstra-Atse, World Cup 2015 (voted the most beautiful game of the tournament). Sijbrands wrote about it in his Volkskrant article on December 24, 2015 and January 2, 2016. Look it up!