Salaman Butt is one of three Pakistan cricketers accused of fixing spot betting markets. ((Emmanuel Dunand/Getty Images))

An anti-corruption tribunal will decide the fate of Pakistan's three leading cricketers when it starts a six-day hearing into spot fixing charges Thursday.

Former captain Salman Butt, Mohammad Asif and Mohammad Amir prepare are preparing to travel to Doha, Qatar, to face the three-man tribunal headed by English lawyer Michael Beloff with South Africa's Justice Albie Sachs and Kenyan Sharad Rao.

The International Cricket Council believes it has prepared a strong case which requires proper scrutiny. If found guilty, the trio could face a life ban.

The ICC suspended Butt, Asif and Amir in September after a British tabloid alleged that they bowled predetermined no-balls during the Lord's test against England.

Beloff rejected appeals by Butt and Amir against the suspension in November. Asif did not appeal.

Pakistan's Twenty20 and one-day captain Shahid Afridi will join coach Waqar Younis as witnesses at the request of the ICC during the tribunal.

Younis told the ICC's code of commission he was surprised when Amir bowled a huge front-foot no-ball, even asking the fast bowler "what the hell was that" during the break.

Afridi said when he met the trio at a hotel room in London he thought they were guilty. Afridi also told reporters on Monday the ICC had lot of important information on the case, but he ill feelings toward his former teammates.

Butt has changed at least three lawyers since his suspension, including Pakistan's former law minister Khalid Ranjha. He will now be represented by London-based lawyer Yasin Patel during Doha hearing.

Amir, who has taken 51 wickets in 14 test matches with his left-arm fast bowling, was confident he would be exonerated.

"My lawyer [Shahid Karim] has prepared a strong case, and with the prayers of millions of fans, I hope the decision will come in our favour," Amir said Tuesday before heading to Doha. "It's a nightmare for me and the toughest test of my life, but I am confident that I will cross through this tough phase."

Butt criticized the ICC for victimizing Pakistan cricketers when his appeal was rejected, while Asif has made no statement since the suspension.

Former Pakistan test batsman Shoaib Mohammad said he hopes the trio will be cleared and able to represent Pakistan at next month's World Cup in South Asia.

"I hope they do," Mohammad told Geo Television. "But if not, I think Amir's absence will be felt the most because of his fearsome pace."

It is not the first time that international cricket has been hit by spot fixing and match fixing. Pakistan's former captain Salim Malik and Ataur Rehman were handed life bans in 1999 by Justice Malik Mohammad Qayyum, who also fined several leading players including Younis and Wasim Akram.

Former Indian captain Mohammad Azharuddin and South Africa's Hansie Cronje, who later died in a plane crash, were also handed similar punishments for their involvement in match fixing.