Proctor picked up a stiff back during Saturday's game at Shrewsbury Town and the striker, who netted his fifth of the season for City at the Greenhous Meadow, was left out of training this Monday as a precaution.
The injury isn't thought to be too severe but Proctor will need to be assessed pre-match ahead of City's clash at the Ricoh Arena, with the likes of James Hanson and Steven Davies waiting in the wings as possible replacements.
City assistant Steve Parkin said: "He's had a bit of treatment on it and we've laid off him a bit today (Monday).
"He's not done any training - he's spent the morning with Matt (Barrass, Head Physio).
"We will leave it as late as possible to assess how he is for tomorrow (Tuesday)."
Even if Proctor is passed fit to play against the Sky Blues though, Parkin admits that City haven't ruled out the possibility of freshen things up given that Tuesday's game will be the club's second in just four days.
Parkin added: "We will taking a lot of time over naming the team and the bench, and it is important we get it right.
"We will have a look to see how the lads are doing in terms of fatigue but there were no injuries after the game apart from Procy (Jamie Proctor).
"All of the lads want to play, especially at this time of year, and that is very encouraging for us."