The Northern Ireland international suffered a recurrence of an ankle problem during the 2-1 win against Blackburn on Saturday.
“It is a recurrence of the ankle injury I had before and is a bit tender,” Evans revealed to the Manchester Evening News.
“I caught it when I kicked the ground during the game. At this point, I don’t know whether I will be fit for the San Siro.
“The doctor said he will have a look at it, and he will have a better picture then.”
Meanwhile Ferguson added: “We are having a nightmare with defenders this season.
“The defenders are being changed all the time. You reach a point when you start to find it hard.”
