Two-goal hero David Nugent has revealed the full extent of his serious neck injury.
City's top-scorer was a surprise inclusion on the subs' bench in Saturday's 4-1 win over East Midlands rivals Derby.
Nugent came on to score twice and make the game – and third in the table – safe for City.
Nugent had been struggling to sleep and was in pain with a slipped disc in his neck.
City boss Nigel Pearson revealed, after the game, that his leading striker's inclusion was a last-minute decision.
Nugent was virtually written off from facing Derby on Thursday, but he improved enough to be named as a sub.
"I didn't think I would be playing but I woke up on Friday morning and my neck felt better," said Nugent.
"It was a slipped disc and it was very painful to start with. I couldn't sleep at night and was taking sleeping pills to try and get to sleep.
"I was going to just do the warm-up on Friday morning and I felt fine, so Dave (Rennie, the physio) asked me to join in with the boxing, so I did and I felt fine.
"Then it was the full training game, and again I felt fine afterwards.
"We had a meeting after training to see if I should go into the squad and I was happy to do that. I wanted to come on and do a job, which I have done and I am delighted.
"It was a pretty serious injury and you just have to rest it. I had a scan on it and there was a bulge, so rest was the key. I haven't trained for two weeks."
Nugent's first goal was a header and he admitted as Ben Marshall's cross came in he was apprehensive about heading it.
"We went to see a neck specialist and he said it would get better day by day," he said.
"It has done and is getting stronger.
"I am still going in for treatment and I am making it stronger to protect it.
"It is pain free now, but I am still a bit weary of it. For the first goal, I was a little scared to go up and head the ball. Once it connected and it felt fine then I got more confident.
"I won a few headers after that. I was waiting for a twinge but nothing came and I came off the pitch pain free."
