Why ball-tampering is such an emotive issue

When umpire Darrell Hair awarded England five penalty runs for Pakistan violating law 42.3 for deliberately altering the condition of the ball during the fourth Test at The Oval, the Australian official provoked a huge Pakistani backlash.

Ball tampering is tantamount to cheating, everything that contravenes the spirit of this most gentlemanly of sports.

Unfortunately these accusations are nothing new to Pakistani cricket.

The slur has taunted the nation since all-rounder Imran Khan first extracted exaggerated late movement with the older ball during the 1970s.

In Cricket's stigma BBC Sport's Troy Cooley examines why ball-tampering is one of the most emotive and controversial issues in Test cricket, especially when accusations involve Pakistan.