Banner Analysis Van IJzendoorn - Verton

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Van IJzendoorn - Verton
The author of this game analysis, Martijn van IJzendoorn (right), in action during his successful world record attempt.
Photograph: Pim Mul

Van IJzendoorn - Verton

„My heart started beating faster for a game of draughts!"

Author: Martijn Ijzendoorn
01-12-2023

These words are written just over a month after breaking the World Record Clock Simultaneous Exhibition. It still feels a bit surreal. The first question many attendees asked afterward was: why did it seem so easy? The fact that I survived the time-pressure phase without any trouble was unexpected. My immediate thought was: next time, there should be at least ten more boards!

To discuss what I consider the most beautiful game of the world record attempt, I’ll first take you through my preparation for the clock simul and how I ultimately decided to take on fifty boards. It all started over a year ago, in early 2022, when Jan Kok called me with a "fun idea." The Hague Open Foundation wanted to organize something in honor of my successful youth career. On the phone, Jan asked if I’d be interested in challenging the world record for clock simultaneous play, which at the time was held by Alexander Georgiev. In 2015, he set the record by playing 45 opponents with a win percentage of over 75%, where 70% was required. When Jan asked how many opponents I would like to face, I immediately replied: "Fifty!"

This impulsive response stemmed from my online experience during the pandemic, where I once played a simul against forty opponents with ease. Many people quickly advised against my choice, arguing that the record limit might be just above fifty, meaning the event could only be organized a few more times. However, I still firmly believe the true limit lies somewhere between sixty and seventy boards, and I'd love to challenge top players to push the record to those numbers!

In my preparation, I received tremendous support from both the organizing team of The Hague Open Foundation and from Koos van Amerongen. Koos organized a practice simul in IJsselstein against thirty players. It was a close call—two opponents kindly offered me draws when I only had a few seconds left on the clock. The main issue was my inability to secure quick victories, which often put me in time trouble. During the second practice simul in Gouda against 28 players, I decided to adopt a more aggressive playing style. This resulted in a score of over 85%, without any time-pressure issues. After this simul, I was confident that the world record attempt was achievable.

Before sharing how I experienced the record-breaking day itself, I must confess something. Here’s what I envisioned beforehand: I’d arrive in Gouda, give a short speech to wish everyone good luck, acknowledging how awesome it was that my opponents came from all over the country for this attempt. Then, once the clocks started, I'd sprint through the room and do my thing. It all sounded relaxed in my head. I'm usually not easily fazed, even during regular games. I always think: this is what I've trained for, and this is what I'm good at. What could go wrong?

But that morning, for the first time in a long while, I felt nervous! All of a sudden, my heart started beating faster for a game of draughts! What's happening? I thought. Walking into the room, I realized the number of boards had nearly doubled compared to the second practice simul. Despite this, the nerves were oddly reassuring. They kept me sharp and gave me extra motivation to break the record. Once the clocks started, I found my rhythm. From that moment, everything-perhaps not effortlessly-went as I had envisioned.

In this analysis, I'd like to guide you through the most fascinating game of the world record attempt. Both technically and tactically, it features numerous remarkable moments. Moreover, over the years, I've developed an unshakable love for the Keller variation, especially when playing as the surrounding side. Throughout this analysis, it will become increasingly clear why.

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Martijn van IJzendoorn - Bert Verton (??-??-????)

1.33-29...Let's start with move 1. Before the clock simul, I decided to aim for sharp positions, as this would increase the chance of achieving quick victories. My choice to open almost every game with 1.34-29 or 1.33-29 immediately led to many interesting flank game positions. 1....17-222.39-3311-173.44-396-114.50-441-65.31-2616-21
6.32-28...The usual way to play the "Keller" is as it unfolds in the game. Also quite popular is the exchange with 6.29-2419x307.35x2420x298.34x2318x299.33x2413-1810.38-339-1311.33-29and fairly new is the following variation: 11....11-16More often, Black plays 11...14-20and it continues as follows: 12.29-2320x2913.23x3410-1414.42-385-1015.34-3014-1916.40-3410-1417.30-2419x3018.34x253-919.47-4214-1920.39-349-1421.34-2922-2822.32x2319x2823.37-3117-2224.26x1712x2125.44-39and so on. 12.42-387-1113.47-423-914.38-3314-2015.42-3810-1416.32-285-10resulting in an interesting position. 6....19-237.28x1914x238.35-3010-149.30-245-1010.37-31...At this point, White also has the option to go for the well-known Van Westerloo variation. However, this is not my preference, as it is quite a forced variation. When Black is familiar with it as well, a well-known draw variation quickly arises on the board after 10.33-2822x3311.39x1914x2312.38-3220-2513.40-359-1414.42-3811-1615.37-3114-1916.44-3919x3017.35x2410-1418.38-3314-1919.45-4019x3020.40-357-1121.35x2423-2822.33x2218x3823.43x32and White really doesn't have much to look for in this position. 10....20-2511.24-2015x2412.29x2014-1913.20-1510-14
14.41-37...With White, you have two moves to choose from at this moment. What I'm doing now is meant to prepare for the exchange 18.34-30 made in the game. It's difficult to explain what the exact advantage of this is, but I believe this exchange mainly prevents the Black center from becoming very strong immediately. Another variation is 14.40-3522-2715.31x2217x2816.26x1712x2117.33x2218x2718.34-3025x3419.39x30but in this variation, Black remains on 23. In certain cases, when a White piece is on 34, an exchange can occur with 23-29. This is often considered troublesome for the surrounding player. 14....22-27I would like to take this moment to express my dissatisfaction with the move that my opponent fortunately didn't play, but is being played more and more frequently: 14...23-2915.33x2419x30Why? Firstly, I consider this a bad move because Black, with proper play, has a beautiful attack after 14...22-27. Secondly, by playing this, Black avoids all the interesting variations that can arise in the battle between attack and surrounding. As a form of protest, I won't elaborate further on this variation. 15.31x2217x2816.26x1712x2117.33x2218x2718.34-3025x3419.40x1813x2220.45-40...
20....11-16At this moment, my opponent voluntarily places a piece on 16. Combined with a piece on 27, this is often seen as weak. However, in this situation, it seems that White cannot take advantage of it with something like 21.37-31, because Black can quickly connect with their attack. A setup like 20...7-1221.40-348-1322.38-3312-18is more common. 21.40-349-1322.34-307-12During the game, I briefly saw a familiar combination that could have arisen if Black had continued here with 22...13-1823.37-31Correct is now 23....18-23but after 23...21-26??White strikes with 24.38-32!26x2825.36-3127x3626.47-4136x3827.43x1+-and after 24.31-26Black can easily simplify with 24....22-2825.26x1727-3226.38x2728-3327.39x2823x1223.44-4012-1824.40-3418-2325.38-333-926.33-2913-1827.39-338-1328.37-3121-2629.43-3926x3730.42x316-11
White has built up their position ideally. The construction with 29/30/33/34/39 ensures that Black is blocked on their long wing. 37-31x31 has just been played to block Black on the short wing as well. Now, Black is forced to play through the center. If Black manages to break free via square 32, with an exchange like 22-27, they are usually in a good position. However, if White is quick enough to counter this, beautiful lock-in variations arise that are often in White's favor. 31.30-25?...This immediately shows how precisely one must play for the surrounding strategy to succeed. It's better to play 31.46-41!and this mainly has to do with the fact that White is now in time to counter all of Black's actions via square 32 effectively: 27-32Two possibilities: A)With 32.48-42?White's advantage immediately disappears after 2-7A1)The best option is to change the direction of the game with 33.30-2419x3034.34x2523x4335.49x2711-1736.41-377-1237.37-3213-1938.32-289-1339.31-2622x3140.36x2719-2441.42-3814-1942.47-4218-2343.15-1023x4344.42-3843x2145.10-524-3046.5x612-1747.6x94x1348.26x1730-35=A2)After 33.31-26?White will even get in trouble: 11-17and now two continuations:
A2a)34.49-437-11and now again a decision point:
A2a1)35.42-38?32-37!36.41x3222-2837.33x2217x3738.36-3137-4239.38-3242-4840.32-2823x3241.31-2732x2142.26x648-37with a poor but still defensible endgame for White. A2a2)Even if White tries to attack the intruder on 32 via square 37, they quickly run into trouble after 35.42-3716-2136.37x2823x3237.47-4219-2338.42-3723-2839.37-3121-27and now White must defend with 40.43-3840.30-25??13-19!32x4341.39x4828x3942.34x43and so on. A2b)Equally impressive is Black's plan if White attacks directly with 34.42-3722-27!35.37x2823x3236.49-43Bad is 36.30-2419x3037.34x2518-22!with the threat of 38...16-21, leaving White out of options on the long wing. 19-23!37.47-4237.33-28?14-19!38.28x3718-2239.29x1817-2140.26x2813x4417-2238.42-3723-28and White must rely on 39.37-31Directly losing is 39.26-21?27-31!40.36x3816x27-+But also 39.30-25?loses after 39....14-19!40.37-317-1241.25-2019-2342.20-149x2043.15x244-1044.24-2010-1445.20x913x4-+16-2140.26x1722x11
41.31x2241.33x22??13-19!42.22x247-1243.31x2232-3744.41x3214-1945.24x139x49-+28x1742.43-3832x4343.39x48with a tenable position for White.
B)Much better is 32.31-26!2-733.48-43and now two options: B1)After 33....7-12?Black will have to play carefully to keep the position balanced: 34.43-38!32x4335.49x3823-2836.41-3719-2337.30-2514-1938.47-4212-1739.38-32
B1a)If Black now thinks they must take the combination with 39....19-24?40.29x2023-2941.34x21Also 41.32x2129x4742.37-31!16x2743.34-2947x2444.20x29leads to the desired result. 16x47, then he loses: B1a1)42.37-31!47x2443.20x2911-1744.25-2028-3245.39-3313-1946.29-2419x3047.20-149x2048.15x354-949.35-309-1350.30-2413-1851.31-27!32x2152.24-19!The only one. 22-2753.19-1427-3254.36-31Continuing with the piece on square 14 also wins. 54....21-2755.31x13!32-3756.13-9!37-4257.9-442-4858.14-10and Black can give up. B1a2)Instead, White must not play 42.33-29?47x2443.20x299-1444.37-3113-1845.29-24and now it is only a draw after 45....11-16!11-17?46.31-27!22x3147.36x27+-because on 46.31-2722x3147.36x27the trick 47....4-10!48.15x414-2049.4x3320x38follows, with a draw as the result. During the analysis, I am constantly amazed at how precisely one must play in order to actually win a game. B1b)Black must defend with 39...9-14!40.42-3814-20!16-21??41.34-30!41.15x2419x3042.29-24!30x1943.25-2019-24*44.20x294-1045.29-2410-1446.34-3013-1947.24x1318x948.30-249-13and White has no better move than 49.37-3128x3750.31x42after which it leads to a draw. B2)Better is 33...11-17, although after the excellent waiting move 34.30-25(Square 42 must absolutely be avoided) all chances remain with White. Black can now respond in two ways:
B2a)34....23-2835.47-4216-21After 35...17-21?36.26x1722x1137.33x2218x2738.42-37!Black loses a piece 36.49-44and now let's look at three continuations:
B2a1)The Black setup with 36....21-27?37.44-40and now 37....7-12?is indeed lost if White now moves the piece from 42 to 31 38.40-3519-2339.35-3013-1940.42-379-1341.37-3114-2042.25x1419x1043.30-24+-B2a2)Also bad, but still a draw, is if Black moves the piece from 7 the other way 36...7-11?37.44-4011-1638.40-3519-2339.42-37now Black must choose:
B2a2a)39....21-27?40.29-24!16-21This position occurred in the game Jos Stokkel-Toine Brouwers 1978. 41.24-2014-1942.35-30+-But not by the move played by Stokkel 42.37-31?Brouwers continued incorrectly with 32-37? and resigned after two more moves. Instead, he should have played 32-38!43.33x4228-33!44.39x2822x33!45.31x1133-3946.26x1739x46to be able to force a draw. B2a2b)39...13-1940.35-309-1341.29-2414-2042.25x1419x1043.24-2021-2744.30-25Strangely enough, the following variation, despite the lock on the board, also offers no winning chances after 44.37-3116-2145.43-38?32x4346.39x4828x3947.34x4323-2848.43-3918-2349.39-3428-3250.30-2432-3851.34-2923x3452.24-1913x2453.20x4038-4254.48x3727-3255.37x2822x3356.41-3733-3957.40-3439x3058.37-32=16-2145.37-3113-1946.34-3046.20-14??19-24!47.14x524-2948.33x2432-3849.43x3228x4650.5x2846x30-+and now Black barely holds a draw with the sacrifice 46...23-2947.33x1318x948.30-2410-1449.39-3428-3350.41-3732x4151.36x4727x3652.34-2922-2853.29x3821-2754.24-1914x2355.20-149x2056.25x1423-2957.14-957.14-1036-4158.47x3628-33=4x1358.15-1036-41!!59.47x3617-22!Only this way. 60.10-528-3361.5-1033x4262.26-2127x1663.10-3742x3164.36x929-34=
B2a3)The best move for Black by far seems to be 36...7-12, especially because Black immediately threatens 19-24 and 32-37 in the position. White can respond in two ways:
B2a3a)At the moment, it is not wise to attack the piece on 32 with 37.42-38?After 21-2738.44-4019-23White must now defend with 39.29-24Bad, but still technically a draw, is the variation with 39.40-35?13-1940.35-309-1341.29-2423-2942.34x2318x2043.15x2413-1844.24x1318x9and so on. 23-2940.34x2318x2041.15x2412-1842.40-3414-1943.24-2018-2344.34-3013-1845.30-2419x3046.25x349-1347.20-1413-1948.14-94x1349.34-3027-31and now for example 50.26x3750.38x27?31-37!51.41x3228x37-+23-2951.33x2419-2352.38x2722x4253.41-3742x3154.36x2717-22=
B2a3b)Therefore, the best move is 37.34-30!After 37....19-2338.36-31Also after 38.42-3823x3439.38x16the position will be a draw. After 39....14-19White must give back the extra piece due to the threat of 19-24! 40.33-2934x23with an equal position 23x3439.31-2722x3140.33x1131-36!41.26x1036x4042.10-534x4343.5x41a draw can be agreed.
B2b)Another forced draw variation occurs after 34...7-1135.43-3832x4336.49x3822-2822-27?37.41-37!17-2238.37-32+-37.33x2218x2738.29x1813x2239.41-3719-2440.38-339-1341.34-2914-2042.25x1422-2843.33x3124x4444.14-1017-2245.10-511-1744-49??46.37-32!49x2747.26-2127-3848.21-17+-46.47-4244-50with a draw
31....11-17It is now possible to continue the attack with 31...27-32!Entering 32 is indeed risky. However, if White is not quick enough to attack 32, it is true that the attack can become quite strong. This is definitely the case after 32.31-2611-1733.46-4123-2834.34-3017-2135.26x1722x1136.33x2218x27and so on. 32.49-4423-2833.44-402-834.40-35...
34....19-23?It is still possible to achieve a good position for Black here, partly due to the infiltration via square 32. After 34...17-21White has two options: A)The variation after 35.29-2419x3036.35x2428-32!37.24-1914x2338.31-2632-3839.26x1938x4040.19-149x2041.25x1440-4542.14-1045-5043.39-34is a draw, but White still has to make it. B)35.34-3028-32B1)Now the move 36.31-26??is always prevented by the combination with 32-38!37.26x2816-2138.33x4218-2339.29x1813x44-+B2)Therefore, White must rely on its defense with 36.47-4121-2637.41-3732x4138.46x378-1239.48-4312-1740.43-3817-21The thematic sacrifice is also a draw 40...27-3241.37x2826x3742.30-2419x3043.35x2416-2144.28-2322-2745.23x1217x846.38-3237x2847.33x3121-2648.31-278-1249.29-2313-1950.24x139x2951.27-224-9=41.30-2419x3042.35x2427-3243.37x1721x1244.31-2726-31=35.31-26?...The plan is to respond to 35...27-32 with 36.29-24! for a good position for White. However, the move played in the game is not the best. Better is 35.29-24!28-32A)17-21?36.24-19!13x2437.31-26and White gains a piece A)Strong seems 36.24-2016-2137.34-30After 37.31-26?White gives up all control over their long wing, and now it is Black who takes the lead after 13-1938.34-308-1339.39-3423-2840.47-4228x3941.34x4322-2823-2838.30-24but the position is not winnable after 38....21-2639.48-4326x3740.43-3832x3441.47-4128x3942.41x322-2843.3-2639-4444.26-3728-3345.37x534-4046.24-1913x2447.20x3840-45=B)Also insufficient for the win is the variation 36.47-418-1237.34-3023-2938.24-2029x3839.15-104x2440.30x1038-43Equally correct is 40...9-1441.10x812x342.41-3732x4143.36x4727x3644.48-4222-2745.42x3327-32with a draw. 41.10-543x3442.5x379-1443.37x518-2344.5x2117x3745.41x3234-39=In these types of positions, where Black is being pushed through the center, it always feels like Black has to survive a certain storm. 35....8-12?
Both sides make mistakes. The actual move is not good because it removes all possibilities with 27-32 and 17-21 from the position. Better is 35...13-1936.46-418-1337.47-4227-3238.41-3732x4139.36x4728-3240.48-4323-2841.47-4119-2342.42-3713-19A)The best move White can play now is 43.29-2419x3044.35x249-1345.41-3632x4146.36x4716-21with an equal position. B)A tricky position arises if White decides to transition into the endgame with 43.43-38?32x4344.39x4828x3045.35x1323x3446.13-834-4047.37-32The logical 47.8-2?40-45and 48.2-7??
is brilliantly prevented after 48....14-20!!49.25x322-2850.7x3245-5051.3x2116x38-+
40-4548.32-2722x3149.26x37and White will have to work hard to manage a draw in the endgame.
36.47-41?...The only explanation I can give for why I didn't play the best move here is that I made a decision in just a few seconds. I thought it was necessary to control the left wing by taking quick action. However, in this case, it would have been better to launch the attack on the other side of the board. Much stronger is 36.29-24!14-19and now White has three options:
A)37.35-30
A1)After 37...28-32it seems White is winning: 38.47-4223-2839.33-299-1440.39-3328x3941.34x4322-2842.24-20Another strong move seems to be 42.46-4119-2343.24-2023x3444.20x9but the position is not winnable after 44....17-2145.26x194x3546.43-3832x4347.48x3035x244-943.43-3919-2344.15-1023x4345.10x812x346.48x39Strangely, White now fails to easily break through the Black wing: 46....18-2347.30-2447.20-149x2048.25x1423-2949.14-1029-34=16-2148.46-4117-2249.26x1722x1150.41-3732x4151.36x4711-1752.20-1517-22=A2)Another possibility for Black is: 37...9-14At this moment A2a)38.47-42is very strong, but technically it seems that after 38...14-2039.25x1419x1040.24-2027-3241.33-2932-3742.42x3110-1443.20x917-2144.26x194x44there is no win to be found. A2b)Another possible continuation is 38.24-204-939.33-2928-3240.29-2422-2832-38?41.47-42!38x4742.15-1014x543.20-1547x2044.25x3+-41.47-4141.36-3127x3642.15-1014x543.47-4136x4744.20-1547x2045.25x317-2246.3x3822-2747.38x2116x2748.30-2519-2449.25-2024-2950.34-3029-3451.39-3334x1452.33x3114-19=18-2242.48-4212-1843.42-3716-2144.15-1014x545.20-1532-3846.37-3228x3747.41x4327-3248.43-3832x4349.39x4822-2850.36-3118-2251.46-419-1452.41-3613-1853.24x1318x954.30-2421-2755.24-2027-3256.15-1032-3857.10x1923x14And amazingly, Black survives this variation as well. B)With 37.24-20White can convert to a favorable endgame: 37....28-3238.47-41Less promising is the following: 38.48-4223-2839.35-3018-2340.30-2419x3041.20-149x2042.15x3512-1843.33-2917-2144.26x1722x1145.25-2016-2146.20-1413-1947.14-94x1348.29-2419x3049.35x2418-2250.24-2023-2951.34x2328x1952.20-1519-2353.47-4123-2854.42-3711-1655.15-1021-2656.39-3426-3157.37x2632-38=23-2839.48-4319-2340.20-149x2041.25x1416-2142.14-1032-3843.33x4223-2944.34x3227x4945.39-3421-2746.34-29and Black must come up with a solid defense. C)The most promising move seems to be 37.34-30!Especially because Black must find an impossible defense with 37....23-29!!If Black does not go for this transition, but continues playing with 37...28-32?the position suddenly loses for Black: 38.47-4223-2839.33-2919-2340.39-349-1441.24-2014-1942.46-4116-2143.42-3732-3844.20-1419x1045.48-4238x4746.29-2447x2047.25x5+-38.24-2029x3839.20-1419x1040.47-4238x4741.30-2447x2042.25x327-32and now a few variations to illustrate why White cannot win: C1)What I find absolutely brilliant is how Black responds after 43.3-25and defends: 43...32-3744.39-34
44.26-2117x2645.48-4237x4846.36-3126x3747.39-3448x3048.25x3222-2749.32x518-2350.5x2116x27=Black can now brilliantly use the following tactical idea to make a draw: 44...4-9!!45.25x322-2746.15x418-2347.4x4223-2948.34x3212-1849.3x2116x47=
C2)Also after 43.3-20it seems that Black is still within the draw limits: 43....18-2344.20-2410-1445.24x232-3846.26-2146.2-2438-4347.24-1343x3448.13x2728-3349.27-4323-2950.43x94x1351.15-1033-39=16x2747.46-4128-3248.41-3732x4149.36x4723-2850.39-3428-33=
36....28-3237.35-30...
37....23-28?It would be wise for Black not to allow 30-24. This move creates an annoying blockade and weakens Black's long wing. A better option is the following: 37...13-1938.41-3732x4139.36x4727-3240.46-419-1341.48-4316-2142.47-42This position actually occurred in the game Yuen Wong-Henk Kalk, 2018. The following moves were played: 42.43-3832x4343.39x4821-2744.41-3727-3245.37x2823x3246.47-4122-2747.48-4217-2248.42-3722-2849.33x3132-38The game later ended in a draw. 23-2843.41-3621-2744.42-3732x4145.36x4728-3246.47-4119-2347.30-2414-1948.25-2019x3049.34x2523x3450.39x3018-2351.43-3951.20-1423-2852.43-3913-1953.14x2328x1954.25-2012-1855.30-2518-2356.39-3423-2857.34-3028x3958.30-2419x3059.25x43=23-2952.33x2427-3153.26x2822x4454.20-1444-4955.14-1013-1956.24x1349-35resulting in an equal draw. 38.30-24!...Black is now truly in trouble, primarily because the inactive piece on 12 is becoming very weak. 38....14-1939.25-2019x3040.34x2513-1941.29-2419x3042.25x3418-23??
Here, Black makes a serious mistake. It's necessary to play 42...9-13but even this looks scary after: 43.34-2913-1944.15-104x2445.29x2018-2346.41-3732x4147.36x4712-1848.20-1523-2949.33x1318x950.26-2117x2651.15-1027-3152.39-3422-2753.34-2931-3654.29-249-1455.10x1928-33Technically, the resulting position does not appear to be a win, but in practice, White certainly has significant chances. 43.41-37?...The full advantage of Black's last move is not exploited. The move I played seemed especially straightforward, and I didn't immediately see how Black could defend against the game plan. Nevertheless, the winning idea should have been: 43.36-31!!27x4744.33-2947x2445.20x38I dismissed this combination because I thought Black would have too much compensation for the lost piece. The computer disagrees with me: 45....12-1846.34-3016-2147.30-249-1348.46-4121-2749.39-3418-2317-2250.48-4313-1951.24x1318x952.34-309-1453.30-24+-50.48-4328-3251.34-3023-2852.30-2517-2153.26x1728-3354.38x2927-3155.41-3631-3756.17-1137-4257.11-713-1958.24x1342-4859.43-3832x4360.13-8+-43....32x4144.46x37...
44....12-18?Luckily, Black gives me a second chance. Just barely a draw is 44...16-21!45.33-29Also 45.37-31is not winning after 45....23-2946.34x3227x2947.20-149x2048.15x3312-1849.33-2922-2850.39-3418-2251.34-304-1052.30-2510-1553.29-2428-3354.25-2033-3955.20-1439-4456.14-944-49=12-1846.37-3127-32!47.48-4347.31-2722x3148.36x38does not win either. 32-3848.43x3228x3749.31x4221-2750.39-3327-3251.42-3732x4152.36x4722-2753.47-4117-2254.41-369-1355.20-1423-28=45.37-31...A quicker path to victory is 45.48-4216-2146.42-389-1347.20-14+-45....28-3246.20-149x2047.15x244-1048.24-2023-2849.48-43...During the game, I realized that I still had to watch out for the following tactical idea: 49.34-29?17-21!50.26x1722x1151.33x1310-1552.31x2215x44=49....16-2150.34-2932-3751.31x4227-3252.42-3732x4153.36x4721-2754.29-2428-3255.20-1518-2356.15x423-2957.43-3832x3458.47-42...
Here, Black resigned due to the combination 58....29x4759.4-1547x2060.15x40
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