Mills' last game was against Liverpool in November

The 27-year-old is back in training after missing eight games with a broken shin, but has been warned not to rush his comeback.

"The scans show there are two big indentations on his shin," City boss Stuart Pearce told the club's website.

"The frustrating thing for Danny is that he feels physically fine, but the medical opinion is 'if you push this too soon, it will break down on you'."

Mills suffered the injury earlier in the season but he played on through the pain until it was diagnosed in November.