When to contact the ball

I just saw the video you did about the plain topspin serve, and how Jeff attack it, I saw Jeff attack it when the ball is going up, not at the top of the bounce, what are the advantages and disadvantages of doing this? I cant get good topspin when I play the stroke early.

Thanks again!

Hi Francisco,

When you hit the ball early you give your opponent less time.  The ball is also travelling faster when it hits your bat so you can get more speed that way.  The disadvantage is that the ball is lower when you hit it and because it is travelling faster it is harder to get the contact right.