Town physio Dave Williams says that Jason De Vos's hairline fracture was missed by an x-ray and only came to light when Canada's medical staff gave him a bone scan. De Vos has been ruled out of Canada's World Cup qualifier with Guatemala and could miss a number of Town games.
The injury, picked up in the recent friendly with Osasuna, is apparently a hairline fracture to the fibula and not to the tibia as previously reported.
Williams told the club site: "Jason had an x-ray on his knee and it was fine. The crack can be invisible on an x-ray but a bone scan showed a small hairline fracture which has obviously ruled him out of playing for Canada.
"I haven't spoken to Jason directly. He is still in Canada and we have missed each other because of the time difference but I will be talking to him later.
"He was due back here on Friday but I'm sure that he will be on an earlier flight now and we will then see the extent of the problem on his return.
"From what I have been told, I wouldn't expect him to be out for much more than a couple of weeks."
Better news for the Blues is that skipper Jim Magilton came through training today without any problems from his injured thigh muscle.