Khan told The Dawn on Sunday that he had personally requested Akhtar to take the field on the third day of the decisive third Test against India and was angered when the Rawalpindi Express refused.
"I asked him what was wrong when he came off the field and requested him to go back and at least field. You saw what happened and I do not have to tell you," said Khan.
The PCB chief pointed out that middle order batsman Asif Kamal on the contrary opted to bat despite heavy pain from an injury.
"There was this boy Asif Kamal who was fighting it out for Pakistan in spite of carrying a serious injury and here was a senior player not bothered by team's plight. This angered me most," he said.
Khan said he was aware that the findings of the four-member medical commission, which he appointed to evaluate the injuries suffered by Shoaib and four other cricketers would not give a conclusive proof.
"But I believe that I must have evidence to confront the players who do not give their best to the country," he said
Khan added that he always sympathised with Shoaib as he was a flamboyant character who made a number of enemies "but on that day he really disappointed me," he said.