In normal Up-and-Back Doubles, the server's net partner takes one side of the court, and in Australian Doubles he or she usually takes the other. But in this variation of Australian Doubles, the server's partner takes neither side. Well, no--not really, but the server's partner makes it impossible to tell which side he or she will take. How? By setting up ambiguously on or next to the centerline.
Like normal Australian Doubles, the I-Formation is a poaching formation that heavily pressures the service return. But in the I-Formation the server's partner does not hide behind the receiver's partner to use him as a block and blind. Instead, he or she positions in the center. Since the server too stations near center, the partners are in line--hence the formation is called the I-Formation. (The name comes from its resemblance to American football's I-Formation, in which the fullback positions right behind the halfback, who positions right behind the quarterback.)
The I-Formation is a variation of Australian Doubles that loses no effectiveness when used repeatedly. That's because, in the I-Formation, you never know which way the server's partner is going to poach.
As in normal Australian Doubles, the ideal serve is the ideal poaching serve--the one down the center to the "T." Serve at the body just often enough to keep the receiver guessing. Serve wide just often enough to keep the receiver honest.
As always, by serving to the "T" you speed your serve, you narrow its Angle of Return, and you insure a return that crosses the net in the center--within a poaching net-partner's reach. Yet serves to the "T" have an added advantage in the I-Formation. By serving to the "T" you put your net partner right in front of the receiver as he or she hits. That is the ideal position. When an up-player fronts an opposing back-player's shot, it is relatively easy for him or her to cut it off.
Hints Department: Whenever the situation lets you quit guarding your alley and front an opposing back-player's shot, do it!
What the Up-Player Does
The I-Formation does not win points by magic. Your up-player doesn't stay parked on the centerline throughout the point. He or she takes one side or the other. At the sound of the serve he or she advances, anticipating the direction of the service return. The goal is to intercept it and volley through The Hole or at the opposing up-player's feet.
Alternatively, the net player can just play Russian Roulette with the receiver by always poaching in a predetermined direction and randomly varying it. Doing this puts excruciating pressure on the service returner and cooks up a delicious match in which, on every point, the service returner and the server's partner eye each other like two boxers at the start of a bout.
As in normal Australian Doubles, the server covers whichever side the net player doesn't.
Like normal Australian Doubles, the I-Formation is an excellent serve-and-volley formation. That's because this strategy minimizes the main risk in following serve--that of having to hit a very low volley or half-volley from no man's land. Not only does I-Formation play make it hard for receivers to place the ball at a net-rushing server's feet, but often the server's partner can protect him or her from that shot by cutting it off.
If possible, DO serve-and-volley often enough to make the receiver watch out for the net rush. I say this because he or she must return serve quite differently when the server rushes than when the server stays back. So, by sometimes following serve you give that poor receiver no less than three things to watch: the ball, your net player, and your server.
Your server is better off knowing in advance which side their net partner will take. Yet when your server stays back, there's little danger in letting your net-player ad lib and having your server just take whichever side their partner doesn't. When the server rushes the net, however, the risk is a little greater. For one thing, your server is in a hurry, and for another, their partner can easily block their view of the approaching ball. So, if you're losing points this way, plan the poaching direction between points, so that your net-rushing server knows which way to go.
How to Keep from Whacking Your Net Player With the Serve
Note that the I-Formation goes against the principle that the up-player should stay out of the back-player's way. That's its major drawback. In the I-Formation, your serves pass very close to your net player, sometimes flying right over her.
You can do two things to minimize the risk of whacking your team's net player with the serve.
First, the net player must get low, and this is of course easier to do if they are short. Also, the net player must not crowd the net. The farther back they sets up, the sooner the ball will pass them, at a point higher in its trajectory. So, you usually see the server's partner about 10 feet (3 meters) from the net: that's about halfway between the net and the service line. (Not that they stays there though. At the sound of the serve they should advance.)
You see I-Formation up-players take some strange Ready Positions. For example, some players spread their feet wide apart, practically doing the side-splits to get low. Others go into a deep knee-bend, practically squatting on their heels or getting down on one knee. If possible, avoid these extreme poses. The I-Formation is FOR poaching the service return, and these Ready Positions are thus counterproductive because they hinder your poacher's movement to the ball.
A very wide stance lengthens the levers that the trunk of the body weighs on, thus greatly increasing the force necessary to move it. Similarly, whenever the butt drops below the knee level, our muscles lose most of their leverage, so it takes much effort to get up and going. Therefore, get low by combining these two methods: spread your feet a little wider and bend your knees a little more, but don't go to extremes in either department. And don't forget that simply bending over at the waist brings you much lower without hindering your movement. In fact, bending over helps movement forward, and you should move forward at the sound of the serve.
The server also bears some responsibility here. As a rule, don't hit flat serves (cannonballs) that barely clear the net. You need a strong American twist or topspin serve. One that clears the net by several feet.
The I-Formation has one other drawback. Being tennis' version of the Triple Option Play, the I-Formation is more complicated than normal Australian Doubles. So, dabbling in it can yield results that remind you of Bob Dylan's song "Mixed Up Confusion." Therefore, don't just experiment with the I-Formation out of the blue. This is a strategy you must discuss with your partner beforehand.
Think of the I-Formation as an instrument of torture. There is no better way to put the screws to a service returner. Since this strategy has so many options that it loses no effectiveness when used repeatedly, if you have the serves and volleys to play it well, you can use it (or mix it with normal Australian Doubles) to keep the opposition perpetually off-balance and not knowing what to expect.