Groenendijk - van IJzendoorn
Jan Groenendijk (l.) and Martijn van IJzendoorn (r.) have known each other from an early age, conquered the draughts Olympus together and fought out many a juicy brawl on the draughts board with varying outcomes. This game forms a beautiful new chapter.
Photograph: G. van Dijk

Groenendijk - van IJzendoorn

To applet

Grandmaster battle to feast on

Author: Wouter Sipma
12-11-2024

The Dutch Championship is one of the greatest tournaments on the draughts calendar. The list of champions holds many important names in draughts history which sometimes have a legendary status (Keller 13-fold champion! Thijssen 5 times in a row!). With his fourth title in a row Jan Groenendijk can be added to this list - what's more, he has a chance to still climb on it.

I've participated in the Dutch Championship since 2013, but was also quite invested in the years before. I can testify that the field of participants is some years better than others. The last few editions can be considered as an absolute top tournament, especially this year with the - incidental - participation of Alexander Shvartsman. Since top players in The Netherlands are top players in the world as well, the tournament should receive worldwide attention (even though I don't know to what extent the tournament is followed abroad).

Different editions stick to my mind because of certain memorable games. Those are quite a few: Baliakin-Boomstra 2010, 2011 and 2013 (as a revenge for Boomstra's lightning fast win in 2009), Baliakin-Meurs 2013 and my defeats versus Groenendijk in 2019 and 2022, as well as my loss against Jitse Slump last year, a game which I analysed before for Damkunst. (While I sum up these games, I notice it mostly concerns Boomstra's and my games; so quite probably it is subjective, but I still believe each and every game were important, on both a technical and sportive level.)

At the start of the game seven rounds had been played, Groenendijk is on top with a +4 score followed by Slump, Shvartsman and Baliakin at +3 and then Van IJzendoorn at +2. Both players are doing well, Groenendijk is in an amazing spot while Van IJzendoorn still has to catch up to make it to the podium. Remarkably, Groenendijk missed a huge chance against Kreeft in the previous round to reach +5. Groenendijk and Van IJzendoorn have known each other from an early age, conquered the draughts Olympus together and fought out many a juicy brawl on the draughts board with varying outcomes. This game forms a beautiful new chapter, both in Dutch Championship history and head-to-head!

Side point: I have commented on this game in two rubrics in Dagblad van het Noorden/Leeuwarder Courant on 7 and 14 October - luckily for Damkunst I can bring some more depth into the variants!

1.31-2617-212.26x1712x21These unusual first moves may seem to indicate that both players do not seek a sharp battle, but at the highest level it may in fact pay off to avoid theory: in this way both players have to think right off the bat and this does not only increase the difficulty, but also complicates time management which may lead to more mistakes later. The next moves show that both players certainly have ambitions. 3.34-3011-174.36-317-125.31-26!?21-27!6.32x2116x27
Black decided to create an outpost on 27 and thus the game has really begun. This position only occurred once, in Sterrenburg-Boomstra (Ereklasse 2017), a game that resulted in a pretty easy victory for Boomstra. Unlike Sterrenburg, Groenendijk is able to create a form of counterplay. 7.40-34...Sterrenburg continued with 7.30-256-118.33-29Two weeks later Sterrenburg reached this position once again (versus Jitse Slump) and this time managed to win. That game is suprisingly similar to Groenendijk-Van IJzendoorn - except for a few pieces, the position after 26 moves is identical! It is striking that Sterrenburg-Slump was also decided in a messy endgame, even though that took 20 moves more... That time Sterrenburg continued with 8.39-3419-239.34-2923x3410.40x2920-2411.29x2015x2420-249.29x2015x2410.37-3211-1611.32x2116x2712.39-3419-2313.38-3310-15offering Boomstra a too strong black centre. 7....6-118.45-4019-239.41-36!?...Groenendijk chooses to reoccupy square 36, after all piece 46 still needs to be developed. Moreover, white wants to postpone decisions on the right wing. 9....14-19Van IJzendoorn continues to strengthen his centre; the seemingly sharper move 9...20-25probably eases white's game plan after 10.33-29Having opened 33, white can pressure 27 via square 32. If we move piece 5 to the other wing (to 6 or 7), this option would have been more interesting for black. 10.46-411-611.50-45...
White played his last waiting move and now black has to show his hand: close square 14 or 22, or play 20-25 after all? Or still wait with 2-7? In the last case white will play 37-31 and black still has to reveal himself. 11....10-1412.30-252-7
This 18x18 I consider a key position - which has occurred 26 times until now - in which the surrounding side is in fact able to create good counterplay facing an open outpost (without a piece on 22), due to the superfluous piece on 5. This position can easily be reached with piece 5 on square 2 (1.32-28 19-23x23 and later 17-21/22 31-26 21/22-27 - or with reversed colours in the Vos variation (1.32-28 18-23 2.33-29 23x32 3.37x28 20-25 4.41-37 12-18 5.29-24 19x30 6.35x24 etc.)), but in my opinion the attacking colour should have the advantage in that case - which doesn't mean that the surrounder is without chances.

Besides, this position can also arise with one tempo difference (black to move) after 1.32-28 20-25 2.37-32 14-20 3.41-37 10-14 4.34-30 25x34 5.39x30 20-25 6.30-24 19x30 7.35x24 etc.

Note: the opening play has had its impact on the clock, after 12 moves both players have less than 60 minutes left from 90 at the start of the game!
13.37-31...The right move to maintain maximal tensions. After 13.34-3020-2414.37-3114-2015.31x2218x2716.25x149x20white is too limited on the right wing. The pseudo sacrifice 17.33-2823x3218.30-25may be answered - due to the presence of piece 5 - by 18....19-2319.25x144-1020.14-93x14and after 21.39-3314-1922.33-2810-1423.28x3715-20black has quite the lead in development (+13 tempi!). 13.33-29also is less logical due to 13....20-2414.29x2015x2415.38-335-10and piece 5 has been activated. 13....20-24An adequate black reply, giving white no grip. 13...17-22limits black's freedom of play 14.34-29or 14.33-2920-2415.29x2015x2416.34-2924x3317.39x17etc. followed by a an assault on 27, regardless of capture. 14...23x3415.40x29(Baliakin-Winkel Ereklasse 2013)
If black tries to keep the position open after 13...17-2114.26x1712x2115.31x2218x27, it will lead to an uncomfortable position after 16.41-378-1217.34-29!23x3418.39x30!, like in Sipma-Heusdens (Riga 2022). 14.31x2218x27
The alternative capture 14...17x2815.33x2218x27is not appealing since black is a passenger; white has 4 attackers versus 3 defenders. 16.41-3713-18Or 11-1717.37-3217-2118.26x1712x2119.32-2823x3220.36-3127x3621.38x16and white should be better because of piece 5 - it needs to be on the other flank in order to build a strong centre. 17.37-3211-1618.32x2116x2719.42-376-1120.47-42!Oege Dijkstra tried to maintain his outpost on 27 against Rik Keurentjes in 2012 after 20....12-17?21.37-328-1222.32x2111-16but could have lost a piece after 23.42-3716x2724.38-33!and black has no defence against 37-31 with a many small combinations. Keurentjes continued 24.37-32and still won later. For example 24...18-2225.34-29!23x3426.40x2015x2427.37-31!7-1128.26-2117x3729.33-2924x3330.39x615.34-29...Groenendijk spent almost 20 minutes on this move; that makes sense, since this choice is decisive for the direction of the game. In my view the most important alternative is 15.42-37A)13-18(or 15...12-18 16.48-42 8-12) 16.48-428-13leading to a new key position (17x17) which has occurred six times.
A1)Krajenbrink (vs. Hein Meijer, Hoofdklasse 1997), Georgiev (vs. Boomstra, WMSG 2011) and Wolff (vs. Kalis, Dutch Championship 2018) continued with 17.34-30A1a)17...18-22This move allows white to change the character of the position. 18.36-31!27x3619.25-2014x3420.40x27
and white is definitely better: his pieces are located centrally and are grouped together, while the black position is not yet connected with stragglers on 6 and 15 and besides that 36 is weak here. 20....13-18Georgiev continued with 21.27-21Krajenbrink chose 21.45-409-1322.40-344-923.37-325-1024.41-3710-14with still a prettier position for white. 5-1022.45-4010-1423.40-3411-16preparing the switch 24.33-2816x2725.28-2217x2826.35-3024x3527.38-3227x3828.42x24keeping the advantage and "after 100 moves Boomstra resigned", according to the title of Sijbrands's rubric in the Volkskrant newspaper of 17-5-2011 discussing this game!
A1b)17...14-20?is bad, because after 18.25x149x2019.33-28!23x3220.37x28black cannot fill all the holes: 20....5-1021.38-3324-2922.33x2420x2923.43-38!A1c)17...17-22is not recommended either, because after 18.33-2923x3419.40x2015x2420.39-335-1021.45-4010-1522.40-3411-1723.34-29black ayway has to flee to the edge using 23....27-3124.29x2015x2425.36x2722x31A1d)Kalis chose the hyper aggressive 3-8?!, perhaps the strongest move: black willingly accepts a severe weakness in his position, but remains hold of the centre. In case white doesn't exploit this weakness, they will be inundated as Wolff had to experience, who in the end got away with a draw. 18.40-345-1019.44-4011-1620.37-31?!Engines recommend 20.37-326-1121.32x2116x2722.41-3720...7-1121.31x2218x2722.49-4413-1823.34-2923x3424.40x2015x2425.39-3417-21!26.26x1712x2127.34-2910-1528.29x2015x2429.44-408-1330.41-3721-2631.43-3911-1732.39-346-1133.37-3217-2134.42-3711-1735.47-424-10Here black missed the remarkable 17-22!36.34-2918-23!!37.29x1824-2938.33x2422-2839.32x2319x28- quite hard to spot. 36.34-29and Wolff survived.
A2)Twice white played 17.37-313-8This is Tansykkuzhina's move vs V. Milshin in the Russian Championship 2005.

In Valneris-Vettner, Baltic champoinship 1991 4-10was played, but this is too skewed (joining Kripans-Stasytis ECh 2024, in which 17...1-6 was the last move). 18.31x2217x28Capturing 18x2719.41-3713-18seems better. 19.33x2218x2720.41-3713-1821.38-338-1322.34-3012-1723.39-3411-1624.34-2923x3425.40x2015x24and white had a better version of the Wolff-Kalis duel: black cannot exchange to 21 in this case and lost eventually.
A3)Lastly, in Baliakin-Meurs, Dutch Championship 2013 (one of those important historic matches!) 17.34-2923x3418.40x2015x2419.33-28was played. It's interesting to compare this version with Groenendijk's choice of 15.34-29, 17.33-28.
A3a)Meurs now continued with the razor sharp 4-10!?20.45-4010-15A3a1)after which white has a choice. Baliakin chose for 21.37-3121...18-2322.31x2223x3223.38x2717x28and did get an interesting surrounding at first, but pushed too far in Meurs's time trouble and even lost in the end.
A3a2)A sharp Roozenburg-type position arises after 21.39-33!?18-2222.37-3112-1823.41-377-1224.37-3224.33-2924x3325.28x3919-23with attack-versus-surrounding is possible as well. 11-1625.32x2116x2726.42-376-1127.37-3211-1628.32x2116x2729.44-39and black appears to be in trouble, becuase after 29....18-2330.39-34!23x3231.34-30!white will play 33-28 at some point, leading to a better endgamee.
A3a3)Engines think the barbaric 21.38-3227x3822.42x33is better for white - perhaps they are right.
A3b)Before you choose Baliakin's variant, you'll have to look your opponent in the eye to be sure 19...3-8won't follow; in that case white should wisely accept the king shot: 20.35-30After 20.45-4018-2321.38-3323x3222.37x2817-2123.26x1711x2224.28x1712x21black has an active position; wit misses the 48-42-37 formation as well as the olympic formation. 24x3521.25-2014x2522.28-2217x2823.38-3227x3824.43x35-1025.42-3810-1426.3x2025x14with equality.
B)Adepts of the Scan engine I recommend the variants 14-20!?16.25x149x20In case white plays (too) automatically 17.48-4217.47-42ensures that 17....4-918.33-2823x3219.37x285-10?is prohibited due to 20.38-32!27x4721.28-22!17x2822.34-2924x3323.48-4247x38Also 17.37-32deserves attention. 17...4-918.33-2823x3219.37x285-1020.38-33then 20....17-2221.28x1711x22they will be disappointed; it is hard to find an active plan for white. Somewhat less logical is 15.41-37since black does not have to make a tempo after 15....13-1816.37-31giving two serious options after 16....8-13without making concessions. 15....23x3416.40x2015x2417.33-2813-1818.38-3317-21!Once again black wisely chooses to keep the position open; the complication 18...18-22?!plays into white's hands, piece 24 will be pressured immediately: 19.39-34!5-1020.44-408-1321.34-3013-1822.40-34and the door to Drost sacrifice heaven is opening up. 18...17-2219.28x1711x22is playable, but severely limits black. The engines don't give up yet: 20.39-34!18-2321.34-29!23x3422.44-4034-3923.43x3427-32!?24.34-29After 24.49-43?follows 32-38!25.43x3222-2826.32x2319x3027.25x34and 24.42-37?isn't possible at all because of 9-13!25.37x1712x2126.26x1724-3027.35x2419x28b+1. 32-3825.29x2038x29with an unclear position. 19.26x1711x2220.28x1712x21
The opening is over; black controls the centre and is ahead in development (5 tempi), but white has targets in 24 and 27. Clock times: 33 minutes for Groenendijk versus 37 for Van IJzendoorn, with 25 moves to go until the time control. That's not a lot!

Both players reinforce their position. 21.39-348-1322.34-3018-2323.44-405-1024.41-373-8!Black shouldn't mindlessly build his position: the following line shows ideas against 24 and 27. 24...13-1825.42-389-1326.43-3910-1527.39-344-9?3-9is the only way, with compensation after 28.34-2923x3429.40x2015x2430.37-317-1231.31x2218x2732.33-2824-2933.48-4212-1834.38-3227x3835.42x246-11etc. etc., but that's tricky to assess from the game position. 28.34-2923x3429.40x2015x2430.37-317-1218-2331.31x2223-2832.33-29!24x4233.22x3331.31x2218x2732.33-28!and white will win a piece.
25.42-386-1126.43-39...
After the opening skirmish we will now get to the next important moment. Groenendijk only has 10 minutes left, against 15 for Van IJzendoorn - the latter thinks for 5 minutes and plays 26....11-17!?Willingly and knowlingly both players approach a breathtaking time scramble with mutual kings! The text move shows Van IJzendoorn is fully committed to play for the win.
26...7-12?is prevented by the simple 27.38-32!27x2928.39-33!29x3829.25-2014x3430.40x27Also 26...13-18fails after 27.39-34!10-15*28.25-20!14x2529.36-31!27x3630.47-41!36x4731.38-32!47x2932.32-2823x4133.34x125x3434.40x2015x2435.1x46The important alternative for the move in the game is 26...11-16A), with the intention to take it a step higher 27.37-3127...23-2828.31x2228x1729.36-31!7-1230.31-2621-2731.48-4213-1832.39-3427-32!33.38x2717-2134.26x1712x32and white has to work to reach a draw. B)or 27.49-4327-32delaying a turn with 13-1828.39-3427-3229.37x2823x3230.38x2721x32is possible as well. 28.37x2823x3229.38x2721x32and white cannot threaten piece 32. 27.49-43...After 27.48-43the same shot as in the game would have been made; according to the evaluation of the engines it does not make a big difference - I think Groenendijk's move is the human way, because the golden piece covers the left wing better than piece 49. 27....21-26
The consequence of black's last move; proceeding with piece 11 27...17-22?was impossible after all due to 28.36-31!27x3629.25-2014x3430.40x1628.37-31!?...Groenendijk accepts the challenge! 28.37-32 17-21 and 28.47-42 17-22 are not interesting for white. 28....26x3729.47-4137x4630.36-3127x3631.38-3246x2832.33x2...
An exciting macro-endgame (or endgame-with-kings?) with 8 minutes for 14 moves for Van IJzendoorn and 5 minutes for 13 moves for Groenendijk! I would have loved to watch this time scramble closely, but I was in a tough battle with Baliakin myself...

Black is one piece up, but has yet to make a king. Also, it is clear that proceeding to king right away will not succeed due to 25-20 and 40x18. White's pieces are rather more situated at the edge of the board (which in principle helps in endgames), but then again black has a nice monolith and can build formations.

The engines don't budge, but for humans it is difficult to play such an endgame correctly. A lot will happen in the time scrable - instead of summing up all analytical possibilities (which are checked by engines anyway), I will try to mainly display human lines.

32....24-29!Strong move - immediately addresses the promotion of piece 36. 32...23-28is less logical because of 33.39-34and 33....36-41?loses after 28-32is possible, even though white will try to get a second king after 34.34-2924x3335.25-2014x3436.40x2734.34-29!24x3335.43-3833x4236.48x4633.43-38...An attempt to block black's promotion with 33.48-4236-4134.42-3741x32is risky; you have to be sure that you didn't give a piece for nothing. 33....36-4134.2-11?!...This move makes sense - white wants to prepare for a black king on 47 - but in fact turns out to be a mistake. Engines recommend 34.38-33!29x3835.30-24!19x3036.35x24to force an endgame with equal pieces after 36....23-2937.24x4241-47But: who dares, wins... 34....41-47?!Van IJzendoorn doesn't make use of his chance! After 34...13-18!(besides 29-34, especially threatens with the sneaky 14-20!!) Groenendijk would have been put under maximum pressure with just 3 minutes for 11 moves. 35.11-29-13A crucial moment:
A)36.40-34?36...29x4037.45x3441-47!and now the black king on 47 is very strong, also after 38.48-4223-28!39.39-33*28x3940.34x4318-22!etc. B)36.39-34?and now 29-33!37.38x2941-47!is most convincing; the white 'Eastern Bloc' (45-40-35-34-30-25) is cut off completely by the king on the 15/47 diagonal (the 'Iron Curtain'?!). C)36.38-32?('variant Eric van Dusseldorp' on Toernooibase) 29-34!37.40x2923x4338.48x3941-47and again the black king holds a great diagonal; moreover the white king is severely limited, it can only move to 16 and is stuck there. 39.2-11??loses on the spot after 18-22!D)36.48-43?and now for example 41-4737.38-3247-4138.32-2729-3339.39x2823x21and black has won a second piece.
E)A draw is only reached by sacrificing a second piece, an option that Groenendijk actually detected during the game: 36.38-33!29x3837.30-24!19x3038.35x24The 24-19 threat is only warded off by 38....14-19and after 39.39-3339.2-16?!19x3040.25x34saves a piece, but after 40....23-2841.16x4918-22(threatens 28-32) 42.49-1641-47black once again holds the strong 15/47 diagonal. 38x2040.25x5we soon reach Kingsrow's database (judgement: draw).
After 40....4-10I haven't found any significant upside of delaying by 41-4741.5x1419x10white still has to find four good moves until the time control. Perhaps in this case the moves may be found relatively easily. 42.40-34!(prevents promotion on 47) 41-4643.2-16!(activates the white king as soon as possible and threaten 16-21). Black is still able to invalidate this threat: 13-1944.16-7!(this move is probably hardest to find, especially in your calculation a few moves back. ) After 44.16-21?8-1345.21-1746-32Kingsrow is not yet convinced of a draw. 8-1245.7-2!and white took back a piece and - almost as important - reach the time control.

Back to the game: 35.11-6!...White has to catch the black king, 35.38-32?is once again followed by 13-18!35....47x5036.40-3429x4037.35x4450x3938.6x44...
After the black king is caught, the game enters the last phase. Both players played their last moves quite quickly and both have about 2.5 minutes for 7 (white) and 8 (black) moves.

White's king costs 3 pieces ('African king') which is positioned quite well: all black pieces are behind the 6/50 diagonal. The threat 44-17 can be tackled in two ways and that's why black should be able to step by step carefully lead his monolith to king.

I think this is the moment Van IJzendoorn loses his grip on the game: not only does he spend half of his remaining time, he also doesn't find the best move - a bad omen.

38....10-1538...13-18is recommended by engines; this prevents the white king from occupying the 4/36 diagonal, which it can in the game. 39.44-35...Groenendijk doesn't play the best move either, but at least plays faster. Stronger is 39.44-22Even though I cannot fully explain this move (I don't want to imagine playing the black pieces against an engine...), I think it's important that after the move in the game 39....23-2940.22-27!will follow and black struggles to activate the trap where the white king lands on square 20, because 13-18 simply cannot be played. After 40....8-1241.27-1613-1842.16-21it turns out black has no trap; still it will be a draw after 42....19-2343.21x823-2844.8-228-3245.2-718-2246.7x3432-3747.34-2314-1948.23x337-41The significance of such computer variations is hard to assess, I call it 'watching monkeys'. 39....23-2939...15-20may seem more logical, but after 40.35-4920-24is prevented: only 4-10stops 49-38, but I wouldn't like to play such a move with time shortage. 41.45-40!24x4442.49x319-2443.3-12and white wins. 40.35-49...Groenendijk plays another relatively fast move (1 minute 25 seconds remaining) - he maximises the action radius of the white king and puts the ball in black's court. 40....13-18With this move Van IJzendoorn dips from 1 minute 8 seconds to 49 seconds for four remaining moves... 41.45-40...Groenendijk spends an considerable amount of time: from 1 minute 25 seconds to 37 seconds. But black now has a lot of options and has to take into account 49-38.

41....9-13Van IJzendoorn finds a solution, but this costs him 35 of his 49 seconds... Another option is 41...18-2242.49-38??29-34!43.40x2943.30x3919-2444.38x2015x2422-27!44.38x39-1345.3x2015x35b+. Groenendijk also has to check all possibilities and with 13 seconds left chooses 42.40-34...After 42.49-38a Turkish capture follows: 42....4-10!43.38x2319x28!42....29x4043.49x35...White has to still make two moves, black three. There is no more for calculations...

43....18-22?After 43...19-23(4-10 and 15-20 are possible, but not obviously so) 44.30-24black is suddenly confronted with 24-19 and the endgame after 44....23-2814-19!?requires superhuman coolness; white has to react because of 15-20, 18-23 after the captures. 45.25-2014x2546.24-1913x2447.35x39could be winning (it's not after 47....15-20*48.39-3420-24*). Pay attention to the golden piece here, which at least makes a lot variations look scary. 44.30-24!19x3045.35x5...This is not what Van IJzendoorn had in mind when he approached the endgame on the 26th move and as a player you feel this - with only 9 seconds for your last move, anything can happen.

45....15-20??On the wretched 45th move everything collapses for Van IJzendoorn. After 45...22-27!46.5-37the black pieces still make it across the main diagonal. One line to illustrate: 46....8-1247.37-2612-1848.26-3718-2249.48-4213-1850.42-3818-2351.37x1927-3152.19-3531-3653.35-194-1054.19x515-2055.25x1436-41and black made it. 46.25x14...
The time control has been reached and Van IJzendoorn could only stare at the board, before he stopped the clock and congratulated Groenendijk. 14-9 is imminent, even after 13-18 (14-9 4x13 5-14! followed by 14-3).

I would like to praise both players for this special game, which pretty much skipped the middle game and jumped from opening to endgame almost right away: in the first place Van IJzendoorn for challenging the player with the fastest calculations at this moment. A draw with Groenendijk is not a bad thing, but Van IJzendoorn went for glory, played superbly and got a great opportunity on the 38th move! The result doesn't bring you anything after a lost heroic battle, but you manifested yourself as a true warrior and only by continuing to try you have a chance to end up at the positive side of the story.

Also Groenendijk deserves praise, of course: not just for beating his great opponent, but also - like in every game - for the courage to fight, even though he is leading the tournament and a draw with Van IJzendoorn is not a problem. To deliver in such battles in the decisive moments (time scramble) makes him the best player right now.

In short: a game to feast on whatever the result and what a pleasure it is to look forward to more of these duels in the future!