Originally Posted by tennis_hack
Wow, you so fierce. U reminding me of Beyonce right now.
Nadal hits topspin moonballs.
Btw, it could be an illusion, but in most of the above 'topspin' backhands, it looks like Djokovic is 'scooping' a bit on them, with a slightly open racket face, yet still a topspin low-to-high swing path. If it is indeed the case that the racket head is slightly open (a degree or so), at contact, does that mean these backhands are completely flat, have topspin on them, or have slice
According to Rod Cross topspin formula:
1. If direction of the racquet velocity is above of the normal to the racquet string bed, then Djokovic hits topspin backhand.
2. If direction of the racquet velocity is below of the normal to the racquet string bed, then Djokovic hits backspin backhand.
This is the main factor that builds ballís spin. Closed or open racquet doesnít create topspin, but changes outgoing ballís trajectory (low or high arc).