Sheffield United defender Lecsinel Jean-Francois faces a further two months on the sidelines after suffering another setback.
The Haiti international had not featured for the Blades this season after sustaining a serious knee injury in a home defeat to Oldham in March, before returning for the final 15 minutes in last week's Johnstone's Paint Trophy win at Notts County.
But the 26-year-old injured his other knee at Meadow Lane and requires surgery to repair the damage.
Blades manager Danny Wilson told the club's official website: "It is bad news for Lecs, he has tweaked his cartilage and looks set to miss around two months.
"We're gutted for him because he'll have to have another operation to clear his knee out. It was such an innocuous collision and now he's back on the sidelines.
"The lad was champing at the bit to play, but that's football and he will come back a stronger and better player."