Skipper Luke Chambers again looks set to be absent when the Blues take on Bristol Rovers at Portman Road on Saturday due to his neck problem, while Danny Rowe is a doubt with his knee injury.
Chambers, 34, is back in training but appears at least a week away from returning to match action.
"He only trained the other day,” manager Paul Lambert said. "I’ve not really seen him head a ball which is a little bit of cause for concern, so we’ll have to wait and see this morning.
"If this one is too soon then hopefully, he’ll be okay for the following one. You just can’t take a risk with someone’s neck.”
Lambert says no risks will be taken with a busy run of fixtures up to and over the Christmas period.
"That’s the bigger picture,” he added. "We have to wait and see. Luke will probably want to play, but we’ve got to look at all of the other games that are going to come up.”
Regarding Danny Rowe, he said: "Danny will still struggle with his knee a little bit. He’ll be a doubt.”
The Blues boss confirmed that Barry Cotter was substituted at half-time against Coventry on Tuesday for tactical reasons rather than due to a knock.
"I just changed it. Barry’s fine, he’s okay, I just gave him another run out with it, but that was just a decision I made at half-time.”
Lambert had praise for Toto Nsiala’s performance against the Sky Blues on Tuesday with the centre-half having had a stop-start season so far due to hamstring injuries.
"The form of all the other lads he’ll [have a] fight [on his hands to get a run in the side], but the good thing for me was he didn’t really train too much before the game and he did well with it, he felt good himself and I think he was one of the lads who came out of the dressing room with a bit of credit.”
Reflecting on Nsiala’s initial injury in pre-season, Lambert added: "It was huge. It was a massive injury for us. It was a blow for us at that point because we had every intention of him starting the season and then the injury happened.
"Then he’s been out for a month with it [again more recently], and that was a blow but touch wood he’s going to be okay.”
Town will be without winger Gwion Edwards against the Pirates as he is banned for one match having picked up his fifth booking at Coventry last weekend.