This is a great example of a player using his whole body to hit a closed-stance forehand.  In this series Novak loads his body by rotating and bending his knees.  Frame 3 shows the end of the loading phase. In frame 4 he lowers the racquet before starting to push from the ground while rotating into the shot.  As you can see his body is facing the net at contact (frame 6).  In frame 7 he continues to rotate while extending his arm forwards before bringing it around on frame 8.

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