Q+A: Cricket - Muttiah Muralitharan's bowling action
Muttiah Muralitharan (file photo) AFP PHOTO/Pal PILLAI.
July 12, 2010 (islandcricket.lk): Muttiah Muralitharan, the most successful bowler in One Day International cricket and Test cricket has announced his retirement.
'Murali,' as he is commonly known is considered by most cricket experts as the best bowler to have ever played the game. But questions continue to be raised over his bowling action especially from Australia where Murali and Australian icon, Shane Warne, fostered healthy rivalry while competing for the world record for the highest number of Test match wickets.
Here are some questions and answers about Muralitharan's bowling action, the testing that cleared him, and the change to chucking laws.
What is chucking or throwing?
Cricket's Law 24.2 and 24.3 states that for a delivery to be legal the ball must not be thrown. Throwing is also known as 'Chucking.' A bowler who is thought to be throwing is considered a 'Chucker,' and to be labeled as such eventually puts an end to a bowler's career.
The laws state that when the bowler's arm reaches the level of the shoulder during delivery, the elbow joint must not straightened partially, or completely from that point until the ball has left the hand.
Flexing or rotating the wrist in the delivery swing is allowed, and bowling with a bent arm is legal as long as the elbow does not straighten from the point the bowler's arm reaches shoulder level.
International cricket matches which includes Test matches, Twenty20 matches (T20) and One Day Internationals (ODI) are not only governed by the basic Laws of cricket mentioned above, but also the International Cricket Council's (ICC) rules and regulations.
The ICC regulations define throwing further by allowing bowlers to flex their elbow joints during delivery by 15 degrees, and it also instructs umpires and other match officials on the process of dealing with bowlers who throw.
Why are there doubts about Muralitharan's action?
Muralitharan was born with a congenital deformity of the elbow which prevents him from straightening his arm. The bent elbow along with incredibly supple wrists, an abnormal shoulder rotation, and the arm speed comparable to that of a fast bowler creates the illusion of a throw.
When Muralitharan was re-tested in 2004 to ascertain if his Doosra delivery was legal, Professor Bruce Elliott from the University of Western Australia, utilising a 12-camera opto-reflective Vicon system operating at 250Hz (fields per second) and 3D motion sensing technology, confirmed that what looked to the human eye as a blatant throw was indeed an optical illusion.
Yet, for some, it was hard to believe that what they were seeing with their own eyes wasn't real.
Who conducted the testing on Muralitharan?
Muralitharan has been tested and cleared to continue bowling four times in all.
He was first tested at the Hong Kong University of Science and Technology in February 1996 under the supervision of Professor Ravindra Goonetilleke in the Ergonomics Division of the university.
The second, third and fourth rounds of testing occurred at the University of Western Australia’s faculty of Life and Physical Sciences (School of Human Movement & Exercise Science) under the supervision of Professor Bruce Elliot.
Did Muralitharan bowl in lab conditions when tested as he would bowl in live match conditions?
Former Australian Test player, Bruce Yardley, who himself was an off spinner in his day, was assigned with the task of ensuring Muralitharan bowled all his deliveries with the same vigour as he would do so in match conditions when tested in 2004.
“His mean delivery speed of 72 km/hr, which is at the higher end of his “test match range” of 65-75 km/hr, shows that he was bowling with intensity in this laboratory environment. The spin bowling expert [Bruce Yardley] also testified to the fact that the deliveries analysed deviated in the appropriate manner with 'venom,' stated the 2004 report from the University of Western Australia.
Where the laws changed to allow Muralitharan to continue playing?
An ICC sanctioned study conducted by Australian bio-mechanist revealed that it was humanly impossible to bowl with a straight arm and that all bowlers breached the laws. The study uncovered that a bowler's arm flexes laterally by nature.
Before the above mentioned study was conducted, the ICC had allocated 10 degrees for fast bowlers, 7.5 degrees for medium pacers, and 5 degrees for spin bowlers which meant that all bowlers were exceeding the stipulated limits.
“Extensive research conducted by the International Cricket Council has revealed that 99% of bowlers in the history of cricket have been chuckers,” the website cricinfo.com reported when the results of the study were first revealed.
The same bio-mechanist from Australia then informed the ICC that the human eye could only detect a throw if the bowler exceeded the 15 degree mark; anything less was not visible to the naked eye.
It then became blatantly obvious that the old regulations needed to be modified.
Click here for the full report released by the University of Western Australia after testing Muralitharan's 'Doosra' delivery in 2004.