Jos Luhukay has confirmed that Kieran Lee has suffered an injury setback following his brief outing for the Under-23s on Monday.
The midfielder, who had made good strides towards a first team return in recent weeks, featured for the Under-23s along with Gary Hooper against Colchester.
But the former Oldham man was withdrawn after 15 minutes with a knee injury.
Luhukay explained: “Kieran was for the first time last Monday in the our Under-23s but could only play 15 minutes after feeling something in his knee.
“He has since had a scan and we must now give him time and patience. He will the next few weeks not be available for us.
“He was on a good way and in a good direction but when you are so long out it can be complicated but he is a positive person with a very good character.
“He is very disappointed of course and this is normal and it will take him time to come back to where he was last week.”
On a more positive note, Hooper played 45 minutes of the PDL2 fixture and is now scheduled to play a part next Monday, as Neil Thompson’s side face Leeds at Middlewood Road.
“Gary Hooper will also take time,” Luhukay added. “He has been out for eight months and played last Monday for 45 minutes, he will next play Monday for 65/70 minutes maximum and we try to come every week further with him.”
Meanwhile, Ash Baker (Wales Under-21s), Atdhe Nuhiu (Kosovo), Michael Hector (Jamaica) and Josh Onomah (England Under-21s) have all returned from international duty in good shape.
Owls new loan duo Hector and Onomah had their first training session with the club on Thursday.