Tuesday, November 1, 2016

Round 7 of 2016 US Tak Open

As we close in on the last match of the Swiss stage, tensions are rising. The last match could make or break a lot of player's inclusion in the next round of the tournament. Regardless of whether you've made it or not, I wish to congratulate all of you who have stuck with the tournament thus far and played through all the rounds. As of the time of writing this, over 360 matches have been finished as a part of the tournament.

This week, I wanted to look a bit deeper into the first game between nebel and r_so9. I've covered neither of these aplayers games but .Based on their current rankings and the game played, though, they seem to represent of mid-tier players. As with my last post, I've included brief, high-level comments on the full game (https://goo.gl/61mf60):

In this week's extended analysis, I wanted to delve a bit deeper into a particular pair of positions. The first position to look at is the game state at the end of the 7th move:

[... 7.c2- Sc3]

In particular, note black's choice to respond with a wall at c3. In the position before placing the wall, it's fairly intuitive that c3 is a pretty important square. This is a connection point for white that black wants to deny. At the same time, it provides defensive protection against white's n-s road threat, which is what is provided by placing at c3. As we'll see, though, a wall here is strictly defensive and limits future offensive potential.

Note that, in particular, part of black's concern may be white's capstone at c2. But, in order for white to capture a c3 flat, white would either have to leave a black stone behind or leave a spot for black to fill with 8. c2' - a good early-game Tak. So, there's no real benefit of a wall placement in particular.

A few plies later and we reach the second position in question:

[7. ... Sc3 8. b1 a3 9. a4]
Here, black has a number of challenges to deal with. White has a pretty decent position and tempo advantage and black doesn't have any really good options to develop tempo himself. As a result, the 'naive' response is to play c3<, blocking white's tempo lead. Alternatively, black could play c4, placing a flat that counters some of whites growing n-s road threat, while developing some loose potential for tempo plays later.

Consider, however, this same sequence of moves, but having played 7. ... c3, as recommended above. in this instance, the position now looks like the following:

[7. ... c3 8. b1 a3 9.a4]

Even though this is a subtle difference, black has a lot more viable options. Within the realm of the previous instance we still have c3< and c4 as strong options, strengthened by the fact that the c3 flat has better offensive potential. However, there's an even better move available for black now: b2+!

[... 9. ... b2+!]

In this iteration, the c3 flat enables black to build a potential w-e road, and gaining a tempo lead - which black can then use to gain future territory and control. In one play through of this, I followed this up with 10. 2c2+ c2 11. 3c3< e2':

[10. 2c2+ c2 11. 3c3< e2':]

Notice how the tempo black achieved, black is able to maintain, keeping pressure, while building control and useful influence points.

Overall, I hope this helps to highlight some qualitative benefit of a flat play over a Wall, and reinforces the idea that, generally, flats are better to play than walls. And that difference often translates to a difference in potential tempo plays, rather than defensive maneuvers.


  1. For move 19. c2+ wasn't an option. It would have yielded a road to black. It also kind of worked out well for the tinue at the end.

    1. Good catch. Looking back at this, I admit some of my initial read was a bit flawed. In retrospect Sd2 here unpinned the white cap, enabling the later move.

  2. Also it should be 24. 2c4+2" b5 since it was white's tinue. Really good analysis though, very helpful and make the game much easier to digest.