No recent cricketer has lived closer to the edge than Pakistan's fast bowler Shoaib Akhtar, the Rawalpindi Express. He has survived injuries, disciplinary problems, questions over the legality of his bowling action and even a positive drug test. Every time he has come back to continue hurling his thunderbolts at the world's best batsmen.This time, though, he looks to have gone too far. He is back in Pakistan, expelled from the squad that will play its first match in the Twenty20 World Cup against Scotland in Durban on Wednesday, after striking Mohammad Asif, another quick bowler, with a bat.He claims he hit Asif by accident after provocation from another Pakistan player, Shahid Afridi. Asif has contradicted his account. The Pakistani authorities will hold an inquiry after the tournament, which runs until Sept. 24.It is hard to see how Shoaib can avoid a career-ending suspension. Striking a teammate with a weapon as dangerous as a cricket bat is about as serious as offenses get within a team.The irony is that it is less than a year since he and Asif were partners not only in Pakistan's battery of quick bowlers but in infamy, as they both tested positive for the steroid nandrolone. Their suspensions were lifted on appeal by a Pakistani court.Both the act of violence and the subsequent disagreement would make it difficult for them to share the same locker room again. This is why Shoaib's international career has probably ended, even if his punishment proves lenient.

He is 32, old for a bowler who relies on extreme pace. Asif is 24; he represents Pakistan's future rather than its immediate past. Shoaib has in the past benefited from some of the indulgence extended to the truly remarkable performer. If such benefits are given to anyone this time, it will be Asif.Shoaib's demise induces the regret that attends any sportsman who brings something distinctive to his game, however reprehensible his actions. It doesn't mean he won't deserve punishment, any more than the former India captain Mohammad Azharuddin should not have been banned for match-fixing or the American football star Michael Vick should have escaped the sanctions accompanying his confession of involvement in dogfighting.But like them, Shoaib will be missed.Nothing in the past decade of cricket has been more exciting than Shoaib charging in from near the boundary at a sprinter's speed, bent on exploring the limits of the humanly possible in delivering a cricket ball at high pace. The memory of his first ball in England remains vivid: Delivered to the West Indian batsman Sherwin Campbell in a 1999 World Cup match at Bristol, it took the edge of the bat and soared over Pakistan's wicket-keeper at extraordinary pace, landing only just inside the boundary.Shoaib deliberately set out to be the first bowler of a delivery timed at 100 miles per hour. He succeeded in 2002. He said he would prefer a short career at maximum pace to a longer one obtained by cutting back to increase accuracy and reduce the strains on his body.Even so, he has lasted a pretty long time. Over 10 years he has played in 43 five-day test matches for Pakistan, taking 169 wickets. Among modern bowlers with substantial test careers, only his prodigious compatriot Waqar Younis has bettered his strike rate of a wicket every 44.7 deliveries. In recent years, he had shown some sense of responsibility, particularly in batting, where he began to play defensive innings in support of specialist batsmen at the other end rather than swinging wildly.He, rather than Kevin Pietersen of England, was cricket's first rock star, with a lifestyle calculated to stir controversy in Islamic Pakistan. Cricket will be duller without him.