James Forrest has a stress fracture of the ankle, Celtic manager Neil Lennon has revealed.
The Scotland winger came off against Riga in the Europa League last month and has not played since. He is expected to miss a further four to six weeks.
Lennon said: "He has a minor stress fracture in the ankle.
"It is remarkable that he played with that for a few games as well, but obviously it got to the point where it was impossible.
"We first thought it didn't show up on scan, but he had a CT scan and it showed a slight stress fracture.
"It is going to take a week or two to settle down then obviously he has to rehab. But the prognosis of the time out will still be the same, roughly four to six weeks."
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