Editing Fair and unfair play (section)

==Ball tampering==
{{main|Ball tampering}}
The state of the ball affects [[delivery (cricket)|deliveries]] to a batsman. Even a new [[cricket ball]] is not perfectly spherical, but in two parts stitched together to form a seam. How a ball moves depends in part on how much air resistance there is to different parts of the ball, and therefore to what degree the ball has deteriorated. A cricket team will normally seek, for example, to polish one side of the ball and rough up the other side. The resulting variation in air resistance on the ball can have a marked effect.{{citation needed|date=October 2017}}

Ball tampering has always been a feature of the sport. Players would use objects to rough up one side of the ball, and use resins and substances like Brylcreem to shine the other. This sort of ball tampering is against the spirit of the game and has always been against the rules. Despite this, it has always gone on with limited sanction, and it can be difficult to spot.

The television age has meant that from the 1990s onwards most international games have been televised. Slow motion replays have highlighted a number of incidents of ball tampering: some of which have been widely reported in the press (such as with the [[Sandpapergate]] incident). The third section of Law 41 contains the rules and sanctions against ball tampering and requires the umpires to make frequent and irregular inspections of the ball to counter it. It also contains punitive measures against fielders who do tamper with the ball. Match suspensions may be implemented.

Some acts that may alter the ball are permitted. A [[Fielding (cricket)|fielder]] may polish the ball as long as no artificial substance is used, remove mud from the ball under the supervision of the umpire and dry a wet ball on a towel. But no-one may rub the ball on the ground for any reason, interfere with any of the seams or the surface of the ball, use any implement, or take any other action whatsoever which is likely to alter the condition of the ball.<ref name=Law41/>

If a player illegally changes the condition of the ball, the umpires replace the ball with another one with similar wear to the old ball before the ball tampering. The umpires also award five [[penalty run]]s to the opposing team and report the incident to the authorities to which the player is responsible. These authorities are then expected to take further disciplinary action against the player as appropriate. If there is a further incidence of ball tampering in the innings the same procedure is followed, but the [[Bowler (cricket)|bowler]] of the immediately preceding ball is banned from bowling further in that [[innings]] too if the tampering was committed by the fielding side.<ref name=Law41/>