4-4 Point 3-3 Invasion, 3-Stone Hane, Switch Sides, Small Knight, Loose Net

Return to parent joseki article: 4-4 Point 3-3 Invasion, 3-Stone Hane, Switch Sides, Small Knight

The 4-4 Point 3-3 Invasion, Three-Stone Hane, Switch Sides, Small Knight, Loose Net is the most common continuation of the three-stone hane shape. Black typically plays the loose net when they are unable to ladder the stone, and this somewhat completes the joseki. The result is considered even for both players.

• White gets a small corner, but they are not yet completely alive
• Black gets the left, and they are essentially alive
• White gets sente, but playing another move locally is a good idea

If White chooses to tenuki, Black has sente moves against the corner that can result in complicated variations that are sensitive to multiple ladders. Professionals often choose to add another move a majority of the time^[1]. Even if White does not play the second small knight immediately, White would like to play it as soon as the ladder becomes favorable for Black, since Black's continuation is more powerful when the ladder is working. Some sources present the added small knight's extension as a part of the joseki. Amateurs who are unfamiliar with the position can be advised to add the second small knight to avoid all complications.

It is important to note that both the and marked stones are not fully captured. The status of these stones is provisionally uncertain. When the ladder favors White (which is usually the case when this joseki is played), White can capture the three stones in gote with the hane at z. However, White usually does not want to do this unnecessarily because taking three stones in gote is small, and Black will become especially thick towards the left. In some joseki variations, Black is willing to discard the three stones. White also has the option to run out the cutting stone, but this is often not a good idea until White is comfortably alive on the top.

Even after the joseki is completed, this position is sensitive to ladders because Black can attack White's position when the ladder favors Black. Without the ladder, the attack is blunted since White always has the option to simply capture the three stones and make definitive life. For this reason, if Black aims to fight or attack White, Black will often play moves in the fuseki to gain the ladder. It is also possible for Black to play a move from the top side even when they lack the ladder, but in those situations, the pincer stone functions as a splitting move rather than a serious attack.

Table of contents Quick Navigation Overview of White Continuations Make Extension Tenuki Overview of Black Continuations Attacking Move Splitting Move Discusion Capturing the three stones is slow Should White tenuki? Breaking the ladder in the fuseki Diagonal Jump, Pincer, or Tenuki? Criticism of the two-space low extension Moving out the cutting stone is not recommended References

Quick Navigation

Moves are listed by frequency in recent professional games^[1], which is sensitive to whole-board position. Bolded moves are commonly considered joseki.

White Continuations  

• a, 4-4 Point 3-3 Invasion, 3-Stone Hane, Switch Sides, Loose Net, Small Knight - (common) (AI favorite) (intermediate)
• t, 4-4 Point 3-3 Invasion, 3-Stone Hane, Switch Sides, Loose Net, Tenuki - (common) (AI favorite) (advanced)
• b, 4-4 Point 3-3 Invasion, 3-Stone Hane, Switch Sides, Loose Net, Two-Space Low Extension - (situational)
• c, 4-4 Point 3-3 Invasion, 3-Stone Hane, Switch Sides, Loose Net, Two-Space High Extension - (situational)
• d, 4-4 Point 3-3 Invasion, 3-Stone Hane, Switch Sides, Loose Net, One-Space Low Extension - (situational)
• x, 4-4 Point 3-3 Invasion, 3-Stone Hane, Switch Sides, Loose Net, Diagonal - (rare/mistake)
• y, 4-4 Point 3-3 Invasion, 3-Stone Hane, Switch Sides, Loose Net, Bump - (rare/mistake)
• z, 4-4 Point 3-3 Invasion, 3-Stone Hane, Switch Sides, Loose Net, Hane - (rare/mistake)

Black Continuations  

• a, 4-4 Point 3-3 Invasion, 3-Stone Hane, Switch Sides, Loose Net, Tenuki, Diagonal Jump - (AI favorite) (advanced)
• b, 4-4 Point 3-3 Invasion, 3-Stone Hane, Switch Sides, Loose Net, Tenuki, One-Space Pincer - (situational)

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Overview of White Continuations

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Make Extension

Make Extension
Small Knight (~55%)	Two-Space Low Extension (~3%)	Two-Space High Extension (~2%)	One-Space Low Extension (2%)

• The small knight extension with (Diagram 1) is the proper move and likely the correct move in a majority of circumstances. This position can be considered to be a type of vital point, as both Black and White would like to occupy this position. If Black obtains it (with a favorable ladder), White is not fully alive, so White would like to be the first one add another move a majority (~55%) of the time. is an effective move to develop the top side.
• Once White plays the small knight extension, the top side is fully alive, so White can consider moving out the stone with a move like z (Diagram 1).
• Professionals have occasionally experimented with other moves, particularly when White does not want to allow at counter-approach at a (Diagram 1) or if there is something interesting to pincer on the top side of the board. In these situations, professionals have have occasionally played the two-space low extension or the one-space low extension. However, these alternate extensions are often criticized by AI and generally not recommended in the AI Weiqi Joseki Dictionary.

Tenuki

White can safely tenuki as long as the ladder is not working for Black (which is usually the case when the joseki is first played).

However, when the ladder works for Black again, returning to play a local move becomes very big. This is because Black's attack is much more severe when they have the ladder. In professional games, it is not unusual for Black to play a move that threatens the ladder, and White will return to play the small knight extension. If Black can get a very good ladder breaker, White may want to consider playing the immediate local extension so that Black cannot get a ladder breaker.

In a sample of ~100 recent professional games (Jan-2022 to Aug-2022)^[1], here is a breakdown of statistics:

• Immediate Small Knight (White): ~55%
• Tenuki, Small Knight or Similar (White): ~17%
• Tenuki, Diagonal Jump/Pincer (Black) (Ladder favors Black): ~2%
• Tenuki, Diagonal Jump/Pincer (Black) (Ladder favors White): ~19%
• Tenuki, Other Move: ~7%

In summary, White does not want Black to play the local follow-up when the ladder works for Black and professionals take measures to ensure that it rarely happens.

Overview of Black Continuations

Attacking Move

Diagonal Jump, Elephant Eye
Elephant Eye	Bad Ladder (Collapse)	Bad Ladder (OK)

• The diagonal jump (or elephant jump) with can be conceptualized as an attacking move when the ladder favors Black.
• The ladder is relevant because jumping in the elephant's eye with (Diagram 1) is an effective counter to , but it only works when White has the ladder (Diagram 2). When the ladder favors White, Black has no good local response to , and in fact tenuki is recommended in the AI Weiqi Joseki Dictionary. Later on, if the ladder favors Black again, Black can resume the attack. For now, White has deflected Black's attack with a move that is difficult to respond to.
• If Black has the ladder, Black can push and cut (Diagram 3), and White has no choice but to slide defensively with to the second line. This is believed to be good for Black.

Diagonal Jump, Kick
Descend	Ascend	Hane

• Another possible response to the diagonal jump is the kick, which invites a difficult fight.
• Black can simply the position with the hane (Diagram 3) to gain outside influence, but it allows White to settle easily.

Diagonal Jump, Attach-Crosscut
Cross-Cut	Black Ladder (A)	Black Ladder (B)	Both Ladders White

• If White has potential to the top right, the attach-crosscut with - can be an excellent move. This move aims to sacrifice the corner for thickness on the outside. However, it is sensitive to multiple ladders.
• The attach-crosscut sequence is useful because White can get a satisfactory result when the main ladder favors Black (Diagram 2).
• However, White must take into account a second ladder arising from the crosscut (Diagram 3).
• If both ladders for White, White can get an especially favorable result.

Splitting Move

One-Space Pincer	Diagonal Jump
One-Space Pincer	Elephant Eye	Elephant Eye, Cont.

• The one-space low pincer with is a simple move that Black can play to get a position on the top side. If White attaches on top and pulls back (Diagram 1), this exposes a cutting point at z. Black can extend at a for influence, protect the cutting with b, or simply tenuki for another move on the top side.
• Previously, we discussed the diagonal jump with (Diagram 2). When the ladder works for White, Black does not have a good local response to , so tenuki is common. In professional games, Black will often play another move on the top side and treat as a free move that Black obtained in sente.
• Professionals have occasionally used this sequence (Diagram 3) to obtain a few more stones on the top side.

Discusion

Capturing the three stones is slow

Capture Variations
Ladder Variation	Ladder Variation	Net Variation

When Black lacks the ladder (Diagram 2), White can capture the three stones in gote with the hane at a (Diagram 1). Black plays the net with , and Black is able to squeeze from the outside (Diagram 3). This result is typically considered good for Black, as Black becomes thick towards the left side. Capturing three stones in gote is slow early on in the game, and White typically does not want to play the hane unless forced to.

It is important to recognize that capturing with the hane at a eliminates the aji that White could later pursue with b or c (Diagram 1). Sometimes, White might prefer the bump at b, which could also allow White to capture the three stones depending on Black's response, or alternatively initiate a fight.

Should White tenuki?

Li Qincheng vs. Fan Yunruo (2018)  

yuzukitea: Generally speaking, Black can comfortably tenuki so long as the ladder does not work for White. If and when the ladder favors White, the small knight's move becomes more valuable (big), and both players would like to occupy it.

This principle is illustrated in Li Qincheng vs. Fan Yunruo. After White played the loose net with , Black chose to tenuki on , which is perfectly reasonable. Both players chose to play several other moves in the opening, before finally White threatened the ladder with . Black's immediate reply is , which is the move recommended by AI.

As a side note, shoulder hit at a is also AI's top recommendation. The shoulder hit would directly threaten the ladder, and in this board position AI thinks Black should tenuki and play the small knight with at . The hypothetical shoulder hit with therefore serves as a ladder breaker, and White can press the corner enclosure on .

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Breaking the ladder in the fuseki

Li Qincheng vs. Fan Tingyu (2018)  

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Diagonal Jump, Pincer, or Tenuki?

Lu Jia vs. Gao Xing (2018)  

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Criticism of the two-space low extension

Two-Space Low Extension  

Miura Taro vs. Tanaka Koyu (2021)  

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Moving out the cutting stone is not recommended

• Kosumi 3% of the time.^[1]
• Bump <1% of time.^[1]

Hong Seong-ji vs. Lee Sedol (2018)  

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References

• [1] ~30,000 professional games downloaded from KifuDepot? from 2018-2022 were used to compute the frequency of moves using the q5go pattern search engine.
• [2] AI Weiqi Joseki Dictionary (2021) - Jiang Weijie
• [3] (Youtube) Michael Redmond: AI Joseki #2 The Direct 3-3 Invasion variation 2 (2020)