A bloke who carries an illegal weapon up his sleeve should look the part. Johan Botha is one such man. There's a glint in his slivered eyes and a grim set to his jaw that warns you not to mess with him and his doosra. It's this delivery - essentially the finger spinner's answer to the wrist spinner's googly - that the ICC has effectively banned Botha from bowling. To use the umpirese for being strongly considered to be chucking, Botha was "reported for a suspect action" during South Africa's one-day series against Australia last month.

The news loomed like a mugger in a dark alley for a player who had risen almost stealthily from mediocrity to the ranks of the respected. His star leapt into fully fledged orbit during South Africa's one-day series in Australia in the first half of 2008-09. He took eight wickets at 23.50, was the most economical bowler on either side, and showed himself to be a nerveless captain in his team's series triumph. Ranked ninth among one-day bowlers early in April, Botha is currently 11th and behind only Muttiah Muralitharan, Daniel Vettori and Shahid Afridi in the spinners' pecking order.

All that meant nothing when he presented himself at the University of Western Australia (UWA) to be tested again. The first time he put his future in the hands of the men in white coats and their protractors - after being reported on his Test debut in Sydney in 2005-06 - he spent 16 months out of the international spotlight finding a remedy for his squiff elbow.

This time almost everything in Botha's armoury passed within the 15 degrees of separation from the straight and narrow, which has been declared legal. The exception was the doosra, which clocked in at a filthy 26.7 degrees. To hear Botha tell it, the demise of his doosra is no great loss. "I haven't bowled it much in the last year," he said. "My other deliveries have become more consistent so there's less of a need to bowl it."

The umpires who reported him, Rudi Koertzen, Brian Jerling and Asoka de Silva, submitted 18 video clips to state their case. Not one of them featured the doosra. And no wonder - Botha is adamant he did not bowl the delivery in the match that led to him being reported.

That wasn't the only unusual aspect of Botha's latest brush with the chucking police. "I was surprised that the doosra was a problem, because your elbow flexes less when you bowl it than with the other deliveries," he said.

The doosra, it seems, makes about as much sense to many of us as Amy Winehouse might do anytime after breakfast. Vincent Barnes, South Africa's bowling coach, took up the challenge to explain the dastardly thing: "It's an extremely difficult ball to bowl because it involves a big bio-mechanical change in a bowler's action. You grip the ball as you would for an orthodox offspinner. But at the point of delivering an offspinner your palm faces the batsman, and the movement of your hand and wrist is similar to what you would do if you were turning a doorknob. If you're bowling the doosra, your palm faces you at the point of delivery."

"There are other guys out there who bowl the doosra who should be sent for testing. Let's see how they shape up under the new regulations"
Mark Boucher

Crucially, Barnes said that "at some stage, you have to bend your arm a little". Botha concurred, but parried skillfully: "You have to bend your elbow to bowl it, but in my case it starts bent and stays that way."

Barnes also offered a fact that only a mother and a coach would know. "Johan's arms aren't straight when they hang by his sides. They are naturally bent at the elbow. He has a natural deformity."

Bruce Elliott, the UWA professor who is also the ICC biomechanist, had made an interesting discovery in his dealings with finger spinners. "He said he had found that a lot of bowlers from the subcontinent could bowl the doosra legally, but not Caucasian bowlers," Barnes said. "Actually a lot of guys bowl the doosra in the nets, but they won't risk it in a match."

Many a bowler would be unnerved at having their grip on the tightrope of legality reduced to a toehold, but not Botha. "One bad delivery could end his career," Barnes said. "It's a very serious thing, and as a team we've had to be strong around him. But he's tough, a thorough professional. The same evening he was reported this time we went through everything and the next morning he was back in the nets, trying to get it right."

Mark Boucher, the wicketkeeper who has to decode Botha's offerings from the other end of the pitch, gave a typically blunt view. "I can pick his doosra, but whether he throws it or not I wouldn't know," Boucher said. "Often when you slow these things down with cameras they look a lot worse than they really are."

Of course Boucher wouldn't be Boucher if he didn't take a swing at someone, in this case Botha's fellow practitioners of the murky art: "There are other guys out there who bowl the doosra who should be sent for testing. Let's see how they shape up under the new regulations."

Botha, who is of sturdy Afrikaner stock, refuses to show as much as a twitch of alarm at what still seems a delicate state of affairs. "You just get on with sorting it out; what else can you do," he said.

Finally a straight arrow of sense in all of this.

Telford Vice is a freelance cricket writer in South Africa