Nightwatchman

A nightwatchman is a lower-order batter promoted up the order late in a day's play, so that a top-order batter does not have to start an innings in the last few overs before stumps.

The logic is about risk. The final overs of a day are a difficult time to begin batting: the light is fading, the bowlers are attacking with nothing to lose, and a wicket then gives the fielding side a psychological lift and a fresh batter to bowl at in the morning. If a wicket falls with, say, twenty minutes left, a captain may send in a number nine to face out the session instead of the number four. If the nightwatchman is out, the team has lost a cheap wicket; if he survives, the specialist batter starts fresh the next morning against tired bowlers.

The tactic is only used in Test and first-class cricket, where play carries over to the next day. It has its critics, who argue that it wastes a wicket and that good batters should back themselves, and some sides refuse to use it. Others have seen a nightwatchman bat through the whole next morning.

In Masterstroke: you can change the batting order at the fall of any wicket, and the clock on the day's play tells you when a nightwatchman is worth the gamble.