Why the return position is the most revealing decision a player makes

The trade the position embodies

A returner standing well behind the baseline gains time to see the ball and to prepare, which makes a fast serve easier to reach. That extra time is purchased with court position, because a deeper return leaves the player further from the middle of the court afterwards. The server gains a longer interval to move into position and a returner already displaced backwards to hit into.

Standing closer reverses both effects, compressing the server's recovery time and leaving the returner in a stronger position for the rally. Neither choice is superior in general, and the correct one depends on the serve being faced and the returner's own capacities.

What a deep position concedes

The wider a returner stands from the middle, the more court is exposed on the opposite side once the return has been struck. A serve angled wide from a deep position drags the returner further off the court than the same serve would from closer in. Servers exploit this by increasing the angle rather than the speed, which costs them nothing and punishes the deep position directly.

This is why a returner retreating against a heavy server sometimes finds that the problem changes shape rather than diminishing. The adjustment has to be paired with a plan for the wide serve or it simply substitutes one difficulty for another.

Why taking the ball early is so demanding

Striking a serve close to the baseline requires beginning the swing before the ball has fully arrived, which leaves almost no room for a misread. It rewards players with compact preparation and excellent anticipation, and it punishes anyone whose technique requires a long backswing. The reward is substantial, because a return struck early arrives while the server is still recovering from the motion.

Players who can do it consistently change what the server is willing to attempt, which alters the match beyond the points actually won. The risk is that a single missed read produces an outright error rather than a defensive ball, so the variance is considerably higher.

Reading what the position admits

A returner who stands in different positions for the first and second serve is stating clearly which of the two he believes he can attack. One who stands identically for both is either extremely confident or has decided that adjusting would give away his intention. Movement between points is equally informative, since a returner drifting steadily backwards through a set is losing the argument.

Servers and their coaches watch exactly this and adjust the pattern of serving to punish whichever position has been adopted. The negotiation is continuous and almost entirely silent, which is why it is invisible to anyone following only the ball.

How the score changes the calculation

At a point where losing the rally ends a game, a returner may accept more risk in order to avoid a long defensive exchange. At a point where the server is under pressure, standing closer applies additional visible pressure without necessarily improving the return. Some players deliberately vary their position on important points purely to disrupt a server's rhythm and preparation.

Whether that works depends on how much the server relies on a settled routine, which varies enormously between individuals. The position is therefore both a technical decision and a piece of communication directed at the player across the net.