Colchester winger Mark Yeates is set to be sidelined for the rest of the season with a dislocated shoulder.
Yeates sustained the injury in Colchester's draw with Sheffield United at the start of the month.
It was initially thought that he would only be out for a few weeks and that surgery would not be required.
However, club medics eventually decided there was no other option and the 22-year-old is now likely to miss the rest of the Championship campaign.
"There was hope that Mark would not need an operation but there was too much uncertainty so we felt that surgery was the best course of action," physio Tony Flynn told the club's official website.
"Having spoken to the surgeon after the operation, this decision proved to be correct with the damage he found and repaired."
Yeates will be unable to train properly for several months but should be back fit in time for pre-season training in July.