A common error made by inexperienced players occurs when the opponent hits it hard at them. Often the instinct is to try and match the pace with like pace. It is very tempting and the occasional (very occasional) time you do hit it back cleanly and hit a (lucky) screaming winner is enough to burn into your memory. Meanwhile, the other 9 out of 10 times this happens you lose the point due to some wild error!
Always remember: tennis is a game of errors. This fact will likely not change any time soon and as long as tennis is a game of errors, one of the most important game-improvement tricks is to find as many ways to limit your errors as possible. On that list, not swinging wildly is way up there.
Watch Roger here at the 2004 Masters Cup against Marat Safin. Safin absolutely crushes a backhand and comes in behind it.
Federer, instead of panicking and taking an unwarranted swipe at the ball, doubly makes sure to set his feet as quickly as possible, get balanced, and hit a nice, controlled shot in reply. His focus is clearly on maintaining balance and form, making clean contact, and merely redirecting the pace Safin provides. Note also the special emphasis Federer places on a clean follow-through and extension.
This is an example of what Federer himself calls “contra-tennis,” meaning, a useful and fundamental style of play based on using what the opponent gives you and redirecting it against him. You don’t fight your opponent; you make him fight himself. It is tennis as judo.
David Nalbandian is the game’s chief practitioner of “contra-tennis,” and watching Nalbandian, you can clearly see that his game is heavily reliant on superior balance and preparation.