Re: Players changing their serving motion.
Serena changed a little bit her service motion, she bends to her knees a lot more, especially on the second serve. But it is good. And most of the times if players want to hit a serve in the wide corner of the service area, then most of the times at the deuce side you see them tossing the ball to the right, but Serena doesn't do that and still she is able to hit those corners, that is what the Belgian commentator said.
And ofcourse Henin too, with not using the full swing on the serve.