Takes
Void
Big Cat
Locking a tennis player in a ball closet for hours is great coaching
[David Ferrer's coach] locked him in a completely dark two meter by two meter ball closet for several hours, giving him only a piece of bread and a bit of water... That's great coaching. That's a football guy in a tennis guy's body.
The effectiveness of such 'coaching' is highly debatable and culturally specific, making it a subjective opinion.