Andrew Davies has been ruled out of City's home fixture with Burton Albion this Saturday (20 April 2013) as the defender continues to be troubled with a calf problem.
There is slightly better news regarding James Meredith, however, with the left back having a fighting chance at present of making City's starting line up for the visit of the Brewers.
Davies had to be replaced after less than half an hour of Tuesday's contest with Rotherham United, while Meredith was substituted early into the second half against the Millers after taking a nasty bang to his hip.
Davies' calf issue, which is believed to stem from a problem in his back, has been troubling the defender for a couple of weeks now.
The former Middlesbrough centre half had already missed last weekend's Chesterfield fixture after pulling out of the warm up with the same problem, but he did train successfully in the build up to Tuesday's Rotherham game.
With City still not completely sure over the exact nature of the injury at present, Parkinson admits getting to the bottom of Davies' problem is a priority.
"Andrew won't make the weekend," confirmed Parkinson.
"Monday (before the Rotherham United game) he trained and Tuesday he was fine as well. He did the warm up and was ready for the game but he seems to still have a problem with his calf.
"He had a scan on his back and his calf yesterday and results were a bit in between really. There was a bit of muscle damage shown but there were also signs that there is a problem coming from his back.
"Our physio will now be liaising with the specialist to see if we can progress Andrew on quickly.
"We are still hopeful it is nothing too major but we need to clear this up promptly because he is obviously in a lot of discomfort."
Speaking regarding Meredith's prospects for Saturday, Parkinson added: "We will give him as long as possible to prove his fitness.
"We have Carl (McHugh), who came on and did well on Tuesday though, so we do have cover if James can't quite make it.
"If James is fit, he'll play, if not, we'll play Carl."