Why does a boxer always move along the direction of the punch of the opponent?

Hint: In order to explain the above statement, we will use the concept of impulse to proof the statement impulse is dependent on the force and the time along with this we will use the classic example of catching the ball which explains the situation of our question and hence we will reach to our answer.

Complete step by step answer:
This technique in which the boxer moves along the direction of the punch of the opponent is called rolling with the punches the science behind this is just same as when we try to catch a ball up in the air directly, we fixes are hand at the time of impact which we directly take all the impulse produce by the ball at same time but if we lower are hand along the ball while catching it then we will feel no force relative to first case
Impulse = change in momentum
 $ {\text{change in momentum = }}\dfrac{{{\text{change in force}}}}{{{\text{time}}}}{\text{ }} $
Hence impulse formula is which we are using to derive the question’s statement is
 $ {\text{impulse = }}\dfrac{{{\text{change in force}}}}{{{\text{time}}}}{\text{ }} $
Using the same example above we can see that when rolling the punch increases the time of impact as we know impulse is inversely proportional to time so increasing the time helps us to reduce impulse and protects the boxer from heavy impulsive punches of the opponent.

Note:
Many of the people will may confuse between the force and the impulse as they same to be equal but the difference is that impulse is force applied at an instance in very short time which is consider as instant force while force is applied for long time therefore time plays important role in force and in impulse it can be ignored as it is negligible