Leon Best picked up a groin strain during the first half of City's 0-0 draw with Reading on Saturday and had to be replaced at the break whilst Jordan Henderson lasted an hour after injuring his foot before being replaced by Isaac Osbourne.
Speaking to the CT, Chris Coleman said: "Leon had a rip in his groin which he felt in the first half and it was getting worse so we had to bring him off at half-time.
Leon Best
"Jordan was also injured, having hurt his foot and we had to take him off as well. Now we have three games coming up this week which are going to be tough with us missing a few bodies but we will get through it like we did before in this situation.
"It is a shame because you want to have all your players fit, so it is unfortunate that we will have three or four that won't be going down to Selhurst Park tomorrow.
"Jordan will be 50-50 at best but Leon won't be fit and David Bell is probably 70-30 in our favour, so fingers crossed."