Head coach David Wagner expects to have both Angus Gunn and Ben Gibson available once again this weekend after both players missed out against Burnley last weekend.
Shot-stopper Gunn picked up a hip injury in training a fortnight ago but has recovered since while Gibson welcomed a son last week.
"Both good. Both were in full training for the week and will be part of the squad for the weekend if nothing extraordinary happens in the last training today," Wagner said.
"Everybody is fine. Marquinhos had some muscle problems but I don't think it is too serious."
The head coach also spoke about the review process following that 3-0 home defeat to Burnley.
He admitted that the analysis was clear but that attention quickly turned to the next challenge.
"We analysed and spoke about the game earlier in the week. It was a normal meeting, what went wrong was clear and obvious," he added.
"It was a clear conversation, it was so clear what went wrong, especially the three goals. It should not happen, we missed a chance to give a statement. We have another big game now against Bristol, it doesn't make sense to focus on Burnley too much."
On this weekend's challenge, Wagner says that his side are looking forward to facing the challenge of a Bristol City side in good form.
Nigel Pearson's men are unbeaten in eight games across league and cup competition.
"It's a team that likes to play football, they are very confident with the run they are on. We have shown the guys what they need to know, given them an idea and solution.
"We have almost 2,500 supporters backing us and we hope to get another good result. It's different going to a stadium away from home when you can feel the energy from your own supporters.
"I'm more than ready to go, I'm pretty sure the guys will be as well. We're excited for it."