The Red Devils host the Romanians in Group C but will be without midfielder pair Cleverley and Young with the former injuring his ankle on the weekend and the latter missing the meeting with Everton on Saturday with a foot/ankle problem of his own.
"Cleverley won't play tomorrow," United boss Sir Alex Ferguson told reporters. "It's not serious but it's one of those injuries where he got a little tweak on it on Saturday.
"We'll look at the long view and make sure he's available for a long period rather than play him again and risk it coming back to haunt us. I think he'll miss Saturday's game also.
"We'll have to make one or two changes tomorrow but hopefully we'll be strong enough."