Aaron Taylor-Sinclair is expected to be out for up to nine months after suffering cruciate knee ligament damage.
The 25-year-old recently underwent surgery after sustaining the injury in Doncaster Rovers’ final game of the season against Burton Albion.
That operation was deemed a success but Rovers have told The Star that they expect Taylor-Sinclair to need around nine months of rehabilitation before returning to action.
Taylor-Sinclair made 49 appearances for Doncaster last term after joining the club from Wigan Athletic on a two-year deal last summer.
The Scot was a regular under boss Darren Ferguson until he was dropped for the penultimate game of the season at Crewe.
It is unclear whether the former Montrose and Partick Thistle defender remained in Ferguson’s plans for next season - the majority of which he will now spend on the sidelines.
Rovers were not blessed with big numbers in defence as it was.
So the injury to Taylor-Sinclair, who played at left back, centre half and also right back over the course of the season, only underlines the need to strengthen in defensive areas.
n A Fan Park - with giant TV screen, street food and fun fair - will be set up next to the Keepmoat Stadium on the day of England’s opening Euro 2016 game against Russia (Saturday, June 11).
Entry will be £2 for adults and 50p for under-12s. See Rovers’ website for more.