Laws of Cricket 1980 Code - Law 22
1. Number of Balls
The ball shall be bowled from each wicket alternatively in overs of either six or eight balls according to agreement before the match.
2. Call of "Over"
When the agreed number of balls has been bowled, and as the ball becomes dead or when it becomes clear to the umpire at the bowler's end that both the fielding side and the batsmen at the wicket have ceased to regard the ball as in play, the umpire shall call "over" before leaving the wicket.
3. No Ball or Wide Ball
Neither a no ball nor a wide ball shall be reckoned as one of the over.
4. Umpire Miscounting
If an umpire miscounts the number of balls, the over as counted by the umpire shall stand.
5. Bowler Changing Ends
A bowler shall be allowed to change ends as often as desired provided only that he does not bowl two overs consecutively in an innings.
6. The Bowler Finishing an Over
A bowler shall finish an over in progress unless he be incapacitated or be suspended under Law 42.8 (The Bowling of Fast Short Pitched Balls), 42.9 (The Bowling of Fast High Full Pitches), 42.10 (Time Wasting) and 42.11 (Players Damaging the Pitch). If an over is left incomplete for any reason at the start of an interval or interruption of play, it shall be finished on the resumption of play.
7. Bowler Incapacitated or Suspended During an Over
If, for any reason, a bowler is incapacitated while running up to bowl the first ball of an over, or is incapacitated or suspended during an over, the umpire shall call and signal "dead ball" and another bowler shall be allowed to bowl or complete the over from the same end, provided only that he shall not bowl two overs, or part thereof, consecutively in one innings.
8. Position of Non-Striker
The batsman at the bowler's end shall normally stand on the opposite side of the wicket to that from which the ball is being delivered, unless a request to do otherwise is granted by the umpire.
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