Amid calls for Rooney to be dropped after a string of uninspiring performances, Mourinho benched the 30-year-old for United’s Premier League clash with Leicester City on Saturday.
United strolled to a 4-1 win over the reigning champions without their skipper, leaving some vindicated in their desire to see Rooney axed.
Mourinho was hoping to recall the forward against Zorya Luhansk at Old Trafford on Thursday, but may keep him under wraps to ensure he avoids more negative press.
“He [Rooney] is selected. I didn’t decide yet if I start with him,” Mourinho told a media conference on Wednesday.
“He didn’t train yesterday, he did just a little bit of a session on Monday. He had a back problem, so today was the first time he did anything with the other players.
“I was completely expecting to use him tomorrow, but I am not sure if I will do that. With his situation I really don’t think he can have a performance which is not really good.
“I am here to protect him, and have to analyse the best thing for him.
“If he is not totally ready for it, I will discuss that with the medical staff.”