Shoaib, 31, pleaded his innocence as the Pakistan Cricket Board (PCB) — due to confirm the results of a B sample today — set up a tribunal to investigate. Mohammad Asif, Shoaib’s new-ball partner in the recent one-day series against England, flew home in similar disgrace before Pakistan’s match against Sri Lanka today.

Having recently signed up to the World Anti-Doping Agency (Wada) guidelines, the PCB will be under pressure to impose the maximum penalty, despite Shoaib’s insistence that any banned substance was taken unwittingly. However, the ICC has no power to increase any ban if it believes that the PCB acts leniently.

Although Malcolm Speed, the ICC chief executive, emphasised that the process is yet to run its course, his description of Shoaib’s impact on cricket sounded ruthlessly like an epitaph. “He has been an entertaining and colourful character,” Speed said. “I think it is up to history to determine how he is remembered.”

Shoaib, aka “the Rawalpindi Express”, has been one of the most controversial players of the past decade, his career punctuated heavily by injuries, a ban for ball-tampering and accusations of throwing. He has also been a spectacular performer and remains the only bowler timed officially at 100mph.

He said last night: “I want to assure everybody that I am innocent of doing anything I should not have done. I have not knowingly taken any performance-enhancing drugs. I would never cheat any team-mate or opponent in this way. I do not feel I need to take drugs to help my bowling."

Tauseef Razzaq, Shoaib’s private doctor, also defended his client. “He does not know anything about medicine,” Razzaq said. “Since he recently suffered ankle and knee injuries he must have taken some medicines which are painkillers but come under the list of banned substances.”

Nineteen Pakistan players were tested in Malaysia on August 26 after Bob Woolmer, the coach, asked the PCB in June to set up a programme before the Champions Trophy. Although the ICC has run drugs tests at events since 2002, this is the first in which the Wada will be adhered to.

Speed said that two players from each side will be randomly chosen to provide samples after six games, themselves picked at random. There is no guarantee that the final on November 5 will be one of them. Pakistan now want to replace Shoaib and Asif, 23, with Yasir Arafat and Abdur Rehman.

Coming after the Brit Oval fiasco, this is more bad publicity for cricket. “If the findings are eventually that the players have broken the code then I think it is disappointing for the game,” Speed admitted. He would not comment on the public perception if Shoaib and Asif play in the World Cup next March.

Woolmer said that he hoped both could feature in the Caribbean and also hinted that the drug might have been in injections given outside the Pakistan medical team while the pair recovered from injury. “I very much doubt whether either player would take this particular substance to enhance performances,” Woolmer said.

Given the involvement of nandrolone, this is more serious than the case of Shane Warne, who was banned for a year in 2003 for taking a diuretic. Ricky Ponting, the Australia captain, described Warne as “very naive or very stupid” and there were slight echoes yesterday in the words of Younis Khan, the acting Pakistan captain.

Younis said: “In today’s situation, players take any small thing and it turns out to be a banned substance. It is all of our responsibilities, players and management. I hope it will not happen again.”

Of the Test-playing nations, England, South Africa, New Zealand, Australia and Pakistan are committed to Wada. Sport England conducts random tests from county to international level on behalf of the ECB.

There is also an anti-doping educational programme run by the Professional Cricketers’ Association and Ian Smith, who was appointed in January as an anti-doping officer, speaks one-to-one with all professionals.

England players were shocked at yesterday’s news. Andrew Strauss said: “Arrogantly or naively, we did not really feel this was something that would come into cricket. As far as I know, it is not commonplace. It is not a game where physical attributes make the difference between winning and losing.”