3-3 Point Invasion/Original

The 3-3 point invasion  

Many weak players fear the invasion of in this diagram. Playing Black, they have the idea that their corner territory is taken away, and are, in a sense, correct. After , it is White rather than Black who will make territory in this corner.

The 2-2 Point Invasion of a 4-4 point at c is typically incorrect, and can be considered a trick play. The idea behind this move is that Black would end up with a heavy group by trying to kill the invasion.

Nevertheless, Black should welcome this invasion. Black shouldn't see this move as an attack on Black's territory; the 4-4 point is not meant to take the corner, but to make thickness and seek a balance between territory and influence. The white invasion at is separated from the rest of the board by the black stone on the 4-4 point. By playing correctly Black will get a strong position. Because of this, stronger players play only if the position on the edges is such that a white stone at a or b will come under attack.

White, for his part, should resist the temptation of invading here too soon. The general principle is that White should seek to invade at the move before black would protect the area.

3-3 Invasion Joseki

The Standard Joseki  

To Black will invariably answer with (or Black at , on the other side). To choose which way to block, the general rule here is to block on the wider side, seeking to maximise the usefulness of the outside strength black is building.
ensures that White's corner will not be too small.

is an important move, preventing white from making progress out into the centre.

White plays at to avoid Black playing at the same point.

is the most usual continuation, although the severe double hane of at 7 is played in some circumstances.

Usually crawling along the 2nd line is bad, but is important to prevent Black turning here in sente. White should resist the temptation to continue crawling at a. Every extra point white takes, is far less valuable than the outside strength that Black takes.

What if B8 plays at "a"?

The joseki continues  

Next, White plays hane at , and the joseki ends with .

White has sente and a few points in the corner, but Black's wall is like a block of concrete, controlling a large part of the board.

This result is regarded as good for Black locally, but is often White's best choice, nonetheless. Later in the game the cut at a might be a problem for Black, see Squeeze for more discussion how and when to defend. See Hovercraft for Black attacks on the corner and the proper defenses.

Can White change the order of play here?

The 3-3 point invasion  

With the knights jump black can get sente, if the upper side isn't very important.

3-3 Invasion Prevention

Prevention  

The usual way to prevent the 3-3 point invasion is a stretch at or a depending on where friendly stones are nearby. The one-space jump at b and the diagonal at c can also be used, though they are seen less frequently.

Preventing the invasion  

This shape is also seen in situations like this, where White has played an approach move, with the same intention of preventing the 3-3 invasion

Overplay (1)  

here instead of in the joseki ( in this diagram) is overdoing things. After , Black has problems.

Overplay (2)  

White could also attack the black stones at the left with these moves. Either way, White has destroyed Black's thickness, and has good chances of getting even more.

Charles I've seen a pro as White play directly at after here.

^tderz: cf. with RTGProblem31

Changing the order  

Here White swaps the order of play, turning at before playing the hane at .

The danger is that Black may be able to answer with rather than the usual . This lets Black shut White into the corner with (particularly as 'a' is Black's sente). White ends up with a smaller corner than in the joseki, and Black may be in a position to make territory on the left. The disadavantage for Black is the aji of the cut at 'b'.

don't let white settle in the corner  

Follow-ups and/or expansions welcome here.

One idea from 10x10CornerGame1 is to let white get the L group in the corner, but not a second eye or connection on the outside.

White shouldn't worry  

Charles Matthews is more than adequate: it makes into quite a bad play ^[5]. White shouldn't fear this.

A more serious attack  

In fact directly, in reply to is a more refined version of this technique. There are a few contexts in which it is strong.

A more serious attack  

Now what?

Charles There is no need to play : just play (1-2-3 principle).

Attacking  

Black can make it unobvious how White lives up to .

Alternate  

erikpan: Just a quick question: Is there anything wrong with ? I've had some success with it, admittedly at the 16k-ish level. When black is already not too strong outside it usually seems possible to live small and steal some territory - unless someone can provide some alternative variations for black?

Answer  

The turn, , is a good play for Black. Not only does it block White in this direction, it threatens a.

Queries  

• at a
• at b (low hane)
• at (double hane)
• at d (inside cut)
• at b
  • (low hane) I
  • (low hane) II
• at c (early second hane)
• 3-3 invading 4-4 plus 3-5
• 3-3 Point - When Does It Work

mat Very often I ask myself if a 3-3 point invasion still works in the presence of more than one black stone. I've set up a page to discuss which of those work and which don't: 3-3 Point - When Does It Work

Black shouldn't worry  

BruceWayne You are right normally, but as the description says, if B has a very strong wall such as the marked stones then W will die.