The new ball spell should be longer than it is

Four overs and off is the modern default, and it wastes the only period of the innings the bowler is genuinely favoured.

Six overs with a hard, lacquered ball in helpful conditions is worth more than any other passage of a Test innings, and captains keep cutting it short.

The pattern is familiar. Opening bowler comes on, beats the edge twice in his second over, looks dangerous through his third and fourth, and then he is replaced because the change bowler has been warming up and it has been four overs and that is what you do. The ball is nineteen overs old before he sees it again, by which time it is doing about a third of what it was.

I understand why it happens. Rotation keeps everyone fresh, the first change deserves a go at a hard ball, and there is a fear of a bowler being milked once the batters are set. All fair. But the underlying asymmetry is being ignored: a new ball moves, and movement is the mechanism by which wickets happen. Everything else is waiting.

The seam is the reason. A new ball has a proud, hard seam that grips the surface on landing, which gives you deviation off the pitch, and it has a rigid enough shape to hold conventional swing in the air. Both of those degrade quickly, and not gradually either. Roughly between overs twelve and twenty the ball loses its bite, and after that the bowler is relying on either reverse, which is a long way off, or the batter making a mistake.

So the spell length should follow the ball, not the clock. If a bowler is on top with a hard ball and the conditions are helping, he bowls until either the ball goes soft or his rhythm goes, and if that means seven or eight overs then it means seven or eight overs. The management of his legs happens later in the day, not now.

The version of this that genuinely costs teams matches is the second new ball. It gets taken as soon as it is available, almost always, regardless of who is bowling or how the batters look. Sometimes the right move is to wait four overs so that your best seamer is fresh when it arrives.

Very few captains do it, because taking the new ball late looks like a decision and taking it on time does not. That is not tactics, that is optics.