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"In a report by scientists commissioned by the ICC it was shown that Pakistani bowler
Shoaib Akhtar and Indian bowler
R. P. Singh were seen to extend their elbow joints by a
negative angle with respect to the upper arm. This phenomenon, also known as
hyperextension, can give the illusion of throwing. In the report it was seen that R. P. Singh maintained this negative angle throughout his delivery stride, while Akhtar sometimes bowled a quicker delivery by flexing this hyperextension. These actions are not considered to be chucking as they are due to the distinctive architecture of their elbows, possibly a congenital condition. Since these cricketers have no control over this hyperextension, any degree of hyperextension (past zero) is not included in the 15-degree extension tolerance threshold."