Why a T20 field is set for the shot the batter wants to play

Restrictions make the field a choice

In the shorter format the number of fielders permitted outside the inner circle is fixed, which means a captain can protect one region well or two regions badly. That constraint changes the nature of field setting entirely, because the question stops being how to stop runs and becomes which runs to allow. A field spread evenly around the boundary looks defensive and is in fact the weakest arrangement, since it covers everything at a distance and nothing properly.

Concentrating the available fielders on one side commits the captain to a bowling plan that must be executed for the field to make sense. The moment the bowler misses his line, that concentration becomes the largest gap on the field and the batter does not need to take any risk to find it.

Offering the shot on purpose

The counterintuitive move is to leave a scoring area open deliberately, because a batter who is offered a familiar shot will usually take it rather than invent one. That converts an unpredictable batter into a predictable one, and a predictable batter can be caught by a fielder positioned for exactly that stroke. The tactic depends on the shot being one the batter plays into the air, which is why it works against power hitters and poorly against timers of the ball.

It also depends on the bowler being able to reproduce the delivery that invites the shot, since a single ball in a different area breaks the trap. When the plan works it looks like a straightforward catch, and the work was done in the arrangement rather than in the delivery.

Denying the strong side rather than the strong shot

Batters in the shortest format tend to have a preferred hitting arc rather than a preferred shot, and the arc is usually visible in their stance. A batter who sets up with an open stance and a slightly closed bat face is telling the captain which half of the ground he intends to use. Placing the available boundary riders across that arc forces him either to hit against his preference or to accept singles into the vacant side.

Both outcomes are acceptable, since a batter hitting against his natural arc makes contact errors and a batter taking singles is not accelerating. The failure comes when a captain reads the arc from what the batter has done rather than from how he is currently standing.

The inner ring does more than save singles

The fielders inside the circle are usually described as saving ones, but in the shortest format their more important job is catching the mishit. A batter attempting a big shot who does not get to the pitch of the ball produces a steepling chance within the ring, and it has to be covered. That is why a captain will often keep a fielder squarer and closer than the run-saving position suggests, because the mishit lands there and the single does not matter.

The trade is explicit and it becomes more favourable as the innings progresses and the batters take on more risk with each ball. Early in an innings the same position is a waste, since batters are not yet swinging hard enough to produce the chance it is waiting for.

Agreeing the plan before the over

A field set for one plan and a bowler executing another is the most common failure in the format, and it happens because the conversation is rushed. The captain and bowler have to agree not only on the first ball but on what happens after a boundary, since that is when plans usually collapse. Bowlers who change their intention after being hit leave a field arranged for a delivery that is no longer being bowled.

The alternative is a pre-agreed second plan with its own field, so the change is a switch between two coherent arrangements rather than an improvisation. Teams that do this well appear calm after a big over, because the response was decided before the over began.