Powerplays are not just attacking phases. They are fielding-restriction phases, and a breach can affect whether a delivery is legal. The exact numbers vary by format and competition, so always check the playing conditions being used.
Powerplays force captains to keep attacking fielders close in certain phases, creating more scoring opportunities and making limited-overs innings less defensive.
Under standard ICC T20 playing conditions, the first six overs of a full 20-over innings form the powerplay. No more than two fielders may stand outside the marked fielding-restriction area during that phase. From the seventh over onward, no more than five may be outside. That changes the captain's options rather than guaranteeing attacking shots: a batter can still be contained by close fielders, changes of pace, and boundary riders placed in the most likely scoring zones. Domestic and short-form competitions may publish different numbers, so the match regulations remain the final authority.
In a standard 50-over ICC men's ODI, overs 1–10 allow no more than two fielders outside the restriction area. Overs 11–40 allow no more than four, and overs 41–50 allow no more than five. The phases apply by over number, not by score, wickets lost, or whether the batting side is attacking. A captain cannot save unused powerplay overs for later. If weather reduces the innings, the playing conditions provide a recalculated phase table; simply taking the same proportions and rounding them informally can produce the wrong limit.
When the scheduled length is reduced before play, officials use the competition's table to set the powerplay and later phases. When an interruption shortens an innings already in progress, the revised point may arrive during an over. The playing conditions explain which restriction applies for the remainder of that over and how the following phases are allocated. Scoreboards usually display the active phase, but captains and umpires work from the official revised innings length. The calculation is independent of a Duckworth-Lewis-Stern target: DLS sets the chase or result target, while the fielding table controls where defenders may stand.
General and competition-specific placement rules can operate alongside a powerplay. These can limit fielders behind square on the leg side, require a minimum number inside the circle, or regulate close-catching positions. A field may therefore have the permitted number of boundary riders and still be illegal for another reason. Count from the instant of delivery, note whether a fielder's grounded position straddles the marked circle, and apply the no-ball consequence stated in the relevant playing conditions.
If the fielding side breaches the restriction, the umpire can call no-ball under the relevant playing conditions. That can also create free-hit consequences in limited-overs cricket.