In the sequence below blue shirt attacks with a punch and gray shirt intercepts the punch with a side kick. The wing chun side kick is primarily used as an interception, and is generally thrown low, to the opponent's knee or shin. Notice that gray shirt begins his side kick interception right as blue shirt begins to move forward. He does not wait for the punch. This is the ideal way to use the side kick as an interception. Attacking the forward movement is faster than waiting for the particular attack.
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