Cricket Ball Maintenance Explained
How fielding teams maintain the cricket ball — polishing, preserving the seam, and the laws governing what is and is not permitted.
Why Ball Maintenance Matters
The condition of the cricket ball directly determines how much a bowler can swing or reverse swing it. A new ball has a lacquered coat and a proud seam; as it ages, one side is polished by the fielding team while the other roughens naturally. This asymmetry creates the pressure differential that causes conventional swing. Maintaining the ball's condition is therefore a legitimate tactical objective for the bowling side.
What Is Permitted
- Polishing the ball with sweat — players may shine the ball using their own perspiration
- Rubbing the ball on the clothing — this maintains the lacquer on one side
- Raising the seam by pressure (within limits) — gently pressing the seam is allowed
- Drying the ball with a towel between overs — preventing damp from softening it
What Is Prohibited (Ball Tampering)
- Applying any artificial substance — lip balm, sweat with additives, sunscreen
- Scratching or gouging the surface — using fingernails, keys, or bottle tops
- Picking or lifting the seam — using fingernails to raise the seam artificially
- Applying saliva — banned since the COVID-19 pandemic in 2020 and retained as a permanent rule
- Rubbing the ball on the ground deliberately to roughen it
The Reverse Swing Connection
Conventional swing requires a smooth side and a rough side — achieved by legitimate maintenance. Reverse swing requires an old, rough ball with one very shiny side, which appears to be a paradox: the shinier side moves toward the batter rather than away as in conventional swing. The laws allow one-sided shine legally; teams that try to accelerate the roughening process through illegal means are attempting to bring forward the reverse swing window unfairly.
Frequently asked questions
Why was saliva banned in cricket?
Saliva was banned during the COVID-19 pandemic in 2020 as a hygiene measure. Subsequent reviews found no material impact on the game and the ICC made the ban permanent in 2022. Sweat is still permitted for ball maintenance.
What happens when a tampered ball is discovered?
The batting side is awarded five penalty runs, the ball is replaced with an equivalent used ball, and the match referee investigates. Players found guilty face match bans and in severe cases longer suspensions.