A concept that continues to linger is that a player who approaches the net should "cover the [down the] line". This principle may have been effective when players use to utilize small-headed, heavy wooden rackets where it was difficult to to flip the wrist and hit it cross court. Nowadays, with improvements in technology, I am not sure if blindly following the "cover the line" rule is such a good idea. A player doesn't have to be Nadal in order to squeeze a tight, cross-court passing shot by the attacking player.

I believe that a better strategy would be for the attacking player to think in terms of BISECTING THE ANGLE. That is, position herself in such as way as to cover just as much of the cross-court as well as the down-the line (and possibly the lob). In addition, the player's chest should be directly square to the opponent's shot (i.e. the shoulders should not be parallel to the net but an angle facing the oncoming ball) thereby enabling the player to move equally fast in either direction.

As a matter of fact, I would recommend moving slightly more towards covering the cross-court and thereby tempt the opponent to go for the low percentage down-the line (i.e. over the high part of the net; "short" side of the court; and, perhaps, while being on a fast run). When attacking with a cross-court, it is important to understand that the opponent's movement to cover the approach coupled with aiming for the down-the line will, in a lot of situation, "vector" the ball out wide. In other words, the momentum of the opponent's movement combined with trying to hit down the line will often result in the ball being "dragged" wide (if only slightly, but wide nonetheless). Therefore, it is often a better strategy to tempt the player to hit the down the line passing shots. If he beats you with shots that go in by mere inches (as opposed to feet), then it was simply her day. However, more likely than not, the chips will fall in your favor when you attack the opponent and force him to take chance after chance by going for the line.

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