Learning from AlphaGo #10: countering the Sakata Opening

hi this is Dave it's been a while since I uploaded my previous video and there are two reasons for that and one I'm quite busy actually lately so it's kind of difficult to find time and secondly it's getting harder to find good topics the AI style openings and joseki are becoming quite popular actually other teachers such as my own teacher in song they cover many topics already and I don't want to overlap with those other lessons but I found a topic that I haven't seen covered elsewhere yet so so I think that's interesting like in my previous video I'm also using leader zero because not all variations are covered in alphago's teaching tool I think Lina is getting pretty close to masters level of course the database was made with 10,000,000 play outs for every move in the database and on my computer I can get maybe 10,000 play outs if I let it think for a couple of minutes so that's still only a small fraction but at least I can just try some alternatives or see some continuations that's good there are some differences between Lina and Master Leela's win rates are a little bit different for example when we start with a empty board master says like as 47% percent win rate so the Komi of seven and a half this may be a little bit too big for black to pay and Lina zero even only gives forty three percent win rates for black it thinks blacks black has an even worse situation overall I get oppression at Lila's Lila's win rates are a bit more pronounced or exaggerated you might say so I try to take that into account when I compare the evaluations of Lila and Master okay for today's topic I chose an opening that was popular in the 1960s you might say oh that's so old-fashioned how can it be relevant today well it's a three three opening for for our stones nowadays get invaded at three three you might be annoyed with that even so one way to avoid that is a three three opening especially with white neither master nor leader thing there's anything wrong with it so let's begin black plays a star point right place and three three black plays another four four and white plays three four points this was fairly common in pro games in the 1960s in particular the professional socata L seem to like this opening was very famous and well-respected Pro in Japan he was one of the most successful players of all time he was very tactical territorial and was famous for his sharp clay and his brilliant to suji his sharply earned him the nickname the razor he liked 33.0 pings and he played this opening several times many of those games were against his great rival takagawa Kaku takagawa Kaku was formed of for four points and thickness so this opening happened quite a few times you might call this white opening the Sakata opening it doesn't have a name as far as I know but I would like to call it the Sakata opening the honor of sakata AO it was not the only one or the first one to play it but it fitted his style I will first start with some of the simpler variations this high approach with a low stone in the lower left corner is quite okay for like white attaches black blocks white moves back black connects and a jump extension and white splits the right side this has been seen in pro games in the 1960s including a game between Sakata and takagawa this is not in masters database and but little things at 44% which for Lila means it's an even game one improvement by Lila is to invade at 3-3 this is in masters database and it's okay for white master things Lila thinks it's only marginally better for white another move for black is to build the left side a little bit bigger white responds and black defends the left side this is not in masters database but I'll just show this one for brevity this move loses nothing for black it's an even game and again white can evade a 3/3 this doesn't matter matter much to approach from this side another even opening this is the casual calm opening with black you can play the high approach a little bit better is a low approach slightly better and also usually played in pro games and master also thinks this is the tightest move one percent better of course AI will respond to this move and also in modern pro games you will find white responding like this this is a good continuation by black calm extension and white continues to build the upper side this is an even position another way for black who is defender of red corner it's an important point this is also a calm opening and it's kind of me I saw white pincers flex approach stone also an even position the best move according to master and leader for black is this is the vital point this is an aggressive continuation the other responses pipe like a fine-toothed so it's a matter of taste if you like fighting and attacking you can play this move and white pincers and black moves out according to master and Leela this is the expected continuation this fight is not over yet black will probably continue to attack two white stones on the left side this isn't even position this is a modern move taken it 1960s when Sakata was playing the normal continuation by White was a two space hypen sir this pincer you don't see it very often nowadays because pincers are now considered overrated under influence of AI they just don't think that painters are really good but in the 1960s this was just the normal move and in sakata's games the normal response would be for like to pay play disk assuming this was a human joseki but plays a night move and black moved to the corner I will show a continuation from a game between Sakata and takagawa white extends on the other side and black attacks fight Spencer stone white ignores it and bills to the lower side black defends the right side and white develops the upper side and jumps to the corner and the game continues from here this position is an even position when I check it with AI master and Leela they feel this move is a little bit suspicious but White's response is also a little bit suspicious so what what are the improvements white should extend more solidly here I think the reason is a black move at a does not hurt white on the upper side so white Spencer stone is from where it's harder for black to attack this is in masters database now attacks it more carefully this continuation is in the database Martha thinks it's okay for white and so does Lila black lost about three percent here so actually this exchange master thing so black shouldn't make that exchange this is a small improvement black still has the option playing at a and white has to worry a little bit about the upside so black can attack the pinch stone this is an even position so if black plays this Kasumi and he continues correctly you will get an even position but a master thinks black has an even better move you may have seen this move this is the shoulder hit kind of signature move of AI to refute pincers against a low three four about approach white pushes like blocks and white cuts they're still human just a key from this this is the suji this is a human joseki a white extends black extends white captures black shoulder head and in exchange like the fuses white Spencer now this is a joseki however Leda thinks this is only 35% win rate for black so it's actually bad some explanation I can come up with marked black stones on the inside while White's mark stone is still on the outside and perhaps also very important white kept sente so this move is a big mistake actually if black continues with the joseki black loses till 12% now the AI move is of course this blocking move just played a lot by master against professionals and Leela also agrees that this is the best move for black and pros also play nowadays it's still very complicated fight I postponed this joseki from my videos I didn't really understand anything about it so I avoided it in my own games my opponents never answered me so I don't know but I got to learn by investigating this with master but backed up with Leela without lil I wouldn't have been able to investigate this very deeply it's so difficult and this is the normal continuation white honest black blocks white connects Atari extend and defend now there are several branches the first move has been seen in pro games perhaps playing against master professionals were still thinking back then this was an over play by black this joseki was just too too dangerous for black so perhaps they were a little bit overconfident and that this was best for a white of course it makes sense to defend the corner the corner group doesn't have an eyes yet so black extends this extension defends against a cut a white cut at a and also black is threatening to jump in at B to take away White's eyes so white blocks and this move I haven't seen in professional games but this is Lina like to play it this is also not in the masters database at least I haven't found it I like this it's kind of the sushi now white this push is threatening to play A or B and black has this nice honey move this gives up the marked cutting stones but in exchange like we'll get a nice outside influence this move threatens white to play at a white and capture the black cutting stones but this move does it in a little bit more efficient way ensuring why it has access to the center and preventing Blanc from squeezing and white pushes guts here so black defends white cuts and now like cutting stones are captured black has some forcing moves according to Leela this is very good for black 60% win rate white has a center but blank sacrifices mark stones well to get a great shape on the outside for the rest of the board so I can understand that this is quite okay for black so perhaps this white move is not the best it loses 8% win rate it's actually quite a big mistake so what then should Y do perhaps it's a smart provide to push here to prevent like getting such a nice outside but this push loses a G and helps like black can still settle his group on the left side and these pushes they give black points on the upside and whites outside shape is still cut in pieces white is too busy and this is also 59% win rate very good for black thanks Leela this fight is not over yet but it's much easier for black so this actually doesn't really work well the best move according to Leela is white clamping here taking the outside leaving the corner vulnerable but it's worth it thanks Leela black defends the upper side and this is a threatening white corner but why it has to cover here to seal like a non the left side black jumps into the corner taking away why its eyes and this is turning into a a call this is 52% win rate for black so it's quite okay if black plays there this is a go forty point go it's actually unavoidable they think that it becomes a KO but from this position it takes two moves to win the whole corner for either side this is 40 points and two moves for either side so it's actually a form of difference that's only ten points per move so this is basically 40 points endgame Kojo Seco so for now I would say this is a split corner both colors have 20 points both can get 20 points extra by adding two moves and black gets a center and I think this is important in the evaluation of this position as okay for black the corner is split whites outside is a little little bit better than blacks but black has center so it's okay for black that's my explanation for this so by going down here both layers play correctly it will become okay for black 52% win rate master and Leela think White has slightly better moves this is masters suggestion ceiling black in on the left black defends his group like can't really push out well if he pushes out here White has center moves against blacks upper side group so black cannot really get out well white box and this is masters suggestion playing a Kasumi white blocks to defend the corner black starts making shape for his crew master wants to cut hair and make eye shape connect here and move out whites upper left corner isn't really fully alive yet white feels the Liberty threatening to play a double Atari at a black defense white pushes if instead white pushes in at a and cuts like crawl seven times to kill the corner that's not really working like extends white tries to play some forcing moves before saving in the corner this fight is not over yet but all the four groups from this original cutting joseki are close to getting settled this is 50% win rate for black actually masters database doesn't contain this position this is where masters variation stops so I had to investigate it a little bit further with Lila Master thinks this is fifty percent win rate and leader fifty-one so it's basically okay for black and this is a Lila continuation fifty percent for black it's okay for black so let's go back a little bit actually this Kasumi it's master suggestion but Lila is not so impressed with this move he that wants to play this move it's much more aggressive it's not a massive database but Lila is quite convinced that this is the best move for black and then I investigated this for hours with Lila and my conclusion for now is that it's also a fifty percent win rate for black basically the same as masters Kasumi but it's much harder for white to keep this 50 percent by blocks in the corner like pushes white blocks and like places Tiger mouth this makes a proper shape you might think well why it doesn't black play this move now but this is risky I will give an example to illustrate the aji push here push and peep connect cut extend and now this is going this is a disaster for black Black has to be very careful after some sufficient play outs the leader thinks this is the proper move for black and now white starts a coal white could push at a but that costs ko threats and it helps like on the other side it's difficult to reach clear conclusions with Leela but my conclusion is that white shouldn't push there and start to ko immediately saving the moves on the upside for the coal disco black cuts and white plays ko like plays disco threat and now white plays this as a KO threat why it saves all quartets so Lina thinks like should take the call now apparently if like response white has one Marco threat is my apophysis and white now captures these stones this local fight is more or less over now but black has a sente and this is 50% win rate this might be the best variation for both if black slides into the corner but it's it can become very complicated with this coal the co is more difficult for white and I think this is the best way for white okay let's go back a little bit so this is masters move clida actually likes this move better to defend the corner its prevents the black slide I mean this slide is prevented little likes that slide very much for black with white it wants to prevent it this is not in masters database I've been looking very hard why this white move is not the best but I cannot really find it I think this is a fine move for white like pushes white has two options white can extend increasing white corner profit and it allows black to take the outside again black has this tsuki this attachment trading the market black stones for the white stone white pushes like blocks and white plays here it's a little bit different from the previous similar variation this ensures white captures two markets black stones in sente and it's more important now for y to capture those stone because White's corner isn't really 100% safe if he doesn't get those stones so white wants to make sure he gets them with this nice the soo-ji like connects and white captures the stones and like finishes his group on the left side so this is sente for white still is 52% win rates for black so it's it's quite okay for black his thick position is very nice it may not be White's best variation but it's fairly simple and it's not so bad for white it's only 2 percent worse than the very best variations for white so you might play this I think a little bit sharper is provide to block here black cannot actually attach at a now because he has fewer liberties on that side and that would be a white cut at B black has to block here now white is alive in the corner so we can play on the outside see you black end on the left side one way to do that is this master like move this is not an masters database but this is only from leader black takes this stone to make eyes white also leaves black has this attachment to settle this group right defense is outside shape first and then blocks and this crosscut fight is a villa continuation this is 53% win rate according to Leela win wait for black this fight is not over yet but I I agree this looks kinda nice for black like still has options to attack white in the center and there's also still options to attack here of course blacks group here is also not fully settled but White has more issues than black I feel so I agree that this is quite okay for black for white is to clamp here we've also seen this before but the corner is a little bit different so what happens now black pushes here once and then but black cannot get out like a get in a cut here the letter is good for black so now make an eye in the corner white leaves and now this looks like a normal move this according to Lee Leela this has 47% win rate so it's okay for black but it loses a 3% actually like it's not that happy because why it is okay on the outside and blacks groups on the upper side and here can be arrests quite a bit by a white like has a better option but this will be a very long sequence like best option according to Leela is to sacrifice everything here playing some forcing moves to to get better shape on the upper side using some exchanges now white needs to defend here this is sente and this shape is important later and for black as we will see black now runs out of course the letter has to be good for black for this to even be possible white the tax black on the left side but like doesn't care black goes for the outside this is sente and sealing white in white kills like screwed now like pushes make some more pushes to make a big wall in this in the middle in the center now white attacks black on the outside and now you will see the usefulness of this shape here it allows black to make a prof Scott here because he can neatly connect his stones so this is according to Lila 50% win rate this was a very long fight but it's actually not that complicated this result might be best for both from this position so this and this both seem to reach 50% win rate for black it's ok for black the conclusion is that this move it's okay for blank still it's not so easy and this pincer may lose about three percent compared to just responding might lose a few percent but it's quite difficult for black does black dare to play this because to get a better result flag has to play this and white can make some very complicated continuation black can do it too but also there are some simpler variations for both colors and actually given this position Lina thinks that this cushion cut is a little bit suspicious enough is to worried that this is not going to end well for a white villa first to avoid this complicated fight with just pushing and continuing like this this is 47% win rate for black and this is a little bit better for white because if white pushes and cuts like it's 50% win rate so it makes sense that Lila prefers this but if you don't push in cuts with whites and maybe it's better for white to not pincer at all and just respond to Black's approach all right a quick summary so this opening for white let's call it the sakata opening to honor socata AO we played this a lot in the 60s a high approach move it's fine especially with this three three stone there's hardly any difference between the high approach move and the low approach move but this is much simpler of course this is a normal continuation and even position from the low approach move the best response for white is to play Knight move and like has three options defend the left side defend the upper side or attack white all three are fine if white plays a pincer which used to be normal until master appeared this loses a little bit it's not that bad but later on like shouldn't slide into the corner and getting this result is even it's much more complicated if black plays the shoulder hit after the pushing cut this used to be joseki but it's actually a mistake this is a bad result for black black should block here this is the normal continuation Master things white should cover here I think this will lead to this position which is 50% when weight for black Lina actually prefers responding here and the best continuation as far as I found is this continuation 50% win rate for black so it's okay for black the shoulder it well that was it thanks for watching bye

4 thoughts on “Learning from AlphaGo #10: countering the Sakata Opening”

  1. Thanks for making this video! I've been trying to study these complicated variations myself, as they keep coming up in my games over the past few months at the 4d level. I feel like most of these variations are harder for black to play than for white, but I'm normally the one playing black in these variations. This video is very helpful for me as a result.

  2. From my analysis with LZ and working with the teaching tool, I don´t think that LZ is close to AGM strength yet. It`s too easy to find positions where LZ can´t find AGM moves, but if you show them to LZ, she realises her mistake. Additionally for opening analysis a large number of playouts is particularly important and LZ is optimized for only 1600 playouts, where as AGM is optimized to work best around 2mio, if I recall correctly.
    Good work on the video though 🙂

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