What are a knuckleball and knuckle serve in table tennis?

What is a table tennis knuckle

Knuckleball in table tennis refers to a non-rotating ball. It is a non-rotating ball or a ball hit with very little rotation that surprises the opponent.

Rotation is a very important factor in table tennis. You can’t win a table tennis match without knowing the rotation. 

Read your opponents rotation and hide your rotation. It can be said that the real pleasure of table tennis is to choose the type of rotation according to the situation.

That is why rotation in table tennis is an important factor.

Dare not rotate

In table tennis competitions where rotation is said to be important, the knuckle is a “ball that does not intentionally rotate“.

Most of the balls hit in table tennis serve and rally are spinning. Meanwhile, by hitting a knuckle that does not spin, you can catch the opponent by surprise and invite a mistake.

For example, it appears to be rotating downward and hits a non-rotating knuckle. If you think that it is a downward rotation and return it with Tsuttsuki (downward rotation), the ball will jump up.

In this way, you can use the knuckleball tactically.

Simple and difficult technique

Many may wonder, “If it doesn’t spin, isn’t it easy?” However, the knuckleball is actually a difficult technique to use.

Rubber is attached to the table tennis racket so that it can be easily rotated. Therefore, if you hit it normally, it will rotate naturally. It is surprisingly difficult to hit without spinning.

To hit the knuckle, you need to hit the ball with a racket.

If you use it incorrectly, you will present a chance ball to the opponent

A knuckle that does not rotate can also become a chance ball for the opponent. It is necessary to strike it so that it is used correctly.

For example, a downward spinning ball has the property of falling downward when hitting a racket. Therefore, the opponent deals by raising the surface of the racket up and hitting it so that the ball does not fall down.

On the contrary, the ball of the upper rotation has the characteristic of jumping up when hitting the racket. The opponent deals with holding the ball with the racket face down so that the ball does not rise up.

On the other hand, a knuckleball that does not rotate can be returned without any special measures. If you know that the opponent is hitting a knuckle, the risk of hitting a smash etc. increases.

When hitting a knuckle, it is necessary to hit the opponent by surprise. Increasing speed, aiming for the course, not to discriminate by mixing with other rotations, etc. Clear tactics are essential when using knuckles.

A knuckle in a bad condition is a great ball for the opponent. If you use a knuckle, you need to be careful to avoid mistakes when using it.

If you feel that it’s difficult to hit when you’re playing with a beginner of table tennis, it’s possible that your opponent is unknowingly hitting the knuckleball. 

Also, when playing table tennis at amusement facilities such as Round One, you may feel that the knuckle is unusually large. The reason is that the rubber of the racket is too worn to rotate. 

In such cases, the more experienced you are, the more confusing you will be.

Knuckle-prone rubber

The knuckle is a batting method that does not apply rotation. Therefore, a rubber that is easy to hit with a knuckle is “hard to rotate.” Specifically, the following three.

  • Table soft rubber
  • Grain height rubber
  • Anti rubber

The surface soft / grain height rubber is characterized by having bumpy protrusions on the surface. 

Since the contact area between the ball and racket is smaller, it is more difficult to spin than the mainstream back soft rubber.

Therefore, the smash has many non-rotating hit balls that are not rotated, such as flicks.

The anti-rubber looks like a soft rubber on the back, but because it has reduced friction, it is extremely hard to rotate. Therefore, a non-rotating knuckle ball is easily hit.

The rubber introduced above is just a rubber that easily produces knuckles. Knuckleballs can be put out even with a soft back that is easy to rotate. 

There is no problem if you can remember that it is the difference in the frequency of hitting the knuckle.

Scenes to hit the knuckle

Here are three main scenes when you hit a knuckleball. I will explain when the knuckle is effective.

  • Mix with the lower rotation serve and hit
  • Speed ​​knuckle serve
  • When you want to change the rally

Mix with the lower rotation serve and hit

As I touched on above, there are many situations where you hit a knuckle while serving. The basic tactic of knuckle serve is to mix it with under rotation and hit it.

By hitting the lower rotation serve and the knuckle serve with the same form, you will prevent the opponent from realizing the rotation. 

If you think that the knuckle is a downward rotation and you Tsuttsuki, the ball goes up, and if you think that a downward rotation is a knuckle and hit it, the ball will hit the net.

Speed ​​knuckle serve

Even after that, the scene where you hit the knuckle when you serve. By hitting a fast and long knuckle serve in a short serve such as downward rotation, you can hit the opponent by surprise.

This is also a basic tactic that is easier for beginners to practice table tennis. The point is Basically, a short serve with a downward rotation and an occasional long serve with a knuckle. 

It is effective to hit the knuckle after the opponent gets used to the short serve.

When you want to change the rally

It is also effective to use a knuckle when you want to have a change during the rally. 

For example, when Tsuttsuki continues, you can hit the knuckle to make it look like Tsuttsuki. If the opponent does not notice it and does the same, the ball will jump up.

As I wrote in the first half of the article, the trick when hitting a knuckle is to surprise your opponent. It is possible to confuse the opponent by suddenly mixing non-rotation in a lot of rotation.

A scene where a knuckle is hit

This time, I will introduce three scenes where the opponent is hit with a knuckle. Let’s be able to deal with the assumption that a knuckle will come.

  • Serve
  • Competing with players using front soft rubber, grain height rubber, and anti-rubber
  • Competition against beginners of table tennis


As I wrote above, there are many situations where a knuckle is struck when serving. 

Be careful not to be at the mercy of your opponent’s knuckle serve. 

Competing with players using front soft rubber, grain height rubber, and anti-rubber

There is a high possibility that the knuckle will be struck when playing against a player using “Table soft rubber”, “Grain height rubber” or “Anti rubber”.

Since it is very different from the competition with the back soft rubber, it is necessary to take appropriate measures. There are few players who use anti-rubber, but there are many who use front soft / grain height rubber.

Competing against table tennis beginners

As I wrote above, sometimes when I am playing against a beginner of table tennis, I sometimes struggle with a knuckleball that is accidentally hit.

There is no problem if you deal with it calmly, but you may feel fresh because the way you fight is different from usual.

How to hit the knuckle

In the video the guy explains how to hit “Knuckle serve” which is closer to non-rotation.

Please check the video (ignore the language) for more details, where you hit the ball during knuckle serve is important. By hitting the ball on the upper side of the ball striking surface, you can hit a knuckle serve that is almost non-rotating.


  • A knuckle is a non-rotating ball
  • Knuckles are often struck when serving
  • The trick to hitting a knuckle is to make a surprise

The knuckle is a simple batting method that a beginner of table tennis accidentally hits, but it is also a very difficult batting method that requires appropriate tactics when used in actual battle.

If you can use the knuckle, the range of the game will greatly expand. 

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