Extension Before Pronation on Forehand?

[keifan]

I think I know the answer to this question but just want confirmation that I am practicing correctly. I assume that extending the hitting hand and arm fully through the ball so that you can eventually end up in a "box" finish occurs well before conscious pronation of the forearm (to start bringing the racquet head across). I realize that a slight amount of pronation is probably going on during the extension phase but I think it is a much smaller component than the forward extension component at that point (just after contact) in the forehand. Basically, my question is... should I hold off on thinking about pronation until I have finished extending the hitting arm forward? That seems to be emphasized by both Jeff and John on this website.

[John Yandell]

Depends on the amount of wiper. for the wiper to be effective, it probably does have to start just before contact. But if you look at Extension and Rotation on the forehand in the Advanced Tennis section, all that is addressed in detail.