It's not that they need a rest now, but if they play every game up until March, they'll be wiped out for the rest of the season, as was shown in the last two seasons for us. There's a reason United always tend to come on strong, it's because Fergie uses opportunities to rest his key players. They don't always need the rest right at that point, but it keeps them fresh throughout the season.
So playing Sandro and Defoe against Maribor has condemned us to a disappointing finish 5+ months from now?
There will be players coming back from injury and some rotation, stop getting your panties in a twist.