Both players were forced off during United's 2-0 win over Everton on Sunday, and it is uncertain as to whether they will be fit to face the Spanish outfit in the last 16 of the Champions League on Wednesday.
However, Ferguson is optimistic that neither player will face a long spell on the sidelines.
"Phil Jones got a kick on the calf and we will have to monitor that," Ferguson explained.
"Jonny Evans got a bit of cramp, and I think he's just lacked a couple of games.
"He only had 45 minutes for Northern Ireland [in midweek]. He had to travel all the way to Malta for 45 minutes, so we will see what he is like."
United face Madrid at the Santiago Bernabeu on Wednesday.