"I have been advised up to two weeks' rest by the doctors after they had a second bone scan of my injury. There is a definite stress fracture in my rib on my lower left side. I will have another examination after the rest period and let us see how it goes," Shoaib told local daily The News from London.
Although Shoaib was unwilling to speculate on his chances of playing for Durham, who are reportedly paying him over eight million rupees for the entire season, sources close to him said that he had already informed the County management that they should start looking for a replacement.
"The very fact that Shoaib himself has told the Durham management about his condition and asked them to look for a replacement does not augur well for his chances of lasting out the season for them," sources were quoted as saying by the daily.
Shoaib said that although doctors had told him that the healing process of his stress fracture would take place naturally, he was not feeling comfortable as yet.
"The fracture is there and it is worrying me. I now want to be 100 per cent sure it has healed before I start playing again. I will resume playing only after I get clearance from the doctors after the next examination in two weeks' time," Shoaib said.
Durham have played a little known Pakistani all-rounder Tahir Mughal in one match as a back up for Shoaib.
The second scan was conducted after Shoaib played a couple of matches for Durham soon after joining them even as the Pakistan Cricket Board (PCB) expressed concern over "such a quick recovery".
The 28-year old has been saddled by injuries and one of them caused him to terminate a County contract with Nottinghamshire a couple of years back.
Shoaib said he was disappointed at not being able to play according to schedule for Durham but expressed his helplesness in the situation.
"After the first few games I was stiff and it was hurting. It was then that I realised that I needed to undergo proper treatment and rest for it to heal," he said.