MasterstrokeMatch play and rules
Powerplay
The opening phase of a limited-overs innings when only two fielders may stand outside the 30-yard circle, and why it sets the tempo of the match.
The powerplay is the phase of a limited-overs innings in which fielding restrictions apply, keeping most of the fielders inside the 30-yard circle.
In a T20 the powerplay is the first six overs, and only two fielders may stand outside the circle. Once it ends, up to five may. In an ODI there are three phases: two fielders out for overs 1 to 10, four for overs 11 to 40, and five for the last ten. In 100-ball cricket the powerplay is the first 25 balls.
With the boundary riders missing, anything hit over or through the ring is likely to go for four, which is why the powerplay is where opening batters attack. It is also the bowling side's best chance of wickets: the new ball swings and seams, and batters trying to clear the infield give catching chances. A side that scores 60 for none in the powerplay has a very different innings ahead of it from one that has crawled to 35 for three.
In Masterstroke: you drag all nine fielders yourself, so the powerplay is where the ring is packed and the batter's green scoring zones are hardest to cover.