Goals from Nani and Javier Hernandez proved enough, despite a late Jobi McAnuff consolation strike.
Here are the player ratings for the Red Devils.
David de Gea: 7
The Spanish shot-stopper wasn't as involved tonight as he was against Real Madrid, but what he did, he did well. Wasn't to blame for McAnuff's goal.
If De Gea continues in this rich vein of form, United will look an infinitely better defensive team.
Phil Jones: 6
Played at right-back after having seriously impressed in recent weeks playing in midfield, Jones wasn't as effective as he could have been.
United fans will be hoping that the injury that saw him subbed before halftime won't keep him out of action for long.
Chris Smalling: 7
With Nemanja Vidic, Jonny Evans and Rio Ferdinand currently considered better options in defence, Chris Smalling needed to impress against Reading.
He was a sturdy, powerful presence at the back, but a little overshadowed by his central partner despite making a crucial late block to deny an equaliser.
Nemanja Vidic: 8
A phenomenal display by the United captain, whose presence in the back line could be key for Sir Alex Ferguson's side down the stretch.
Made some stunning blocks and last-ditch headers that kept Reading from threatening. A Serbian beast.
Alexander Buttner: 7
The Dutch left-back earned a rare start for the Red Devils in place of the exceptionally fit Patrice Evra.
He performed well, patrolling his wing with confidence going forward and keeping his opposite number in check on the back foot.
Antonio Valencia: 7
Tony V had an underwhelming first half, struggling to get into the game. But with Nani's arrival on the scene and his subsequent move to right-back, Valencia looked far more impressive.
This isn't to say he should make the switch permanent, just that he is a capable fill-in if and when the time comes.
Tom Cleverley: 7
One of the Red Devils' most improved players this season, Cleverley was in fine form against Reading on Monday night.
With a conventional two-man central midfield, the Englishman's fantastic movement and passing in tight situations was much appreciated.
Anderson displayed plenty of energy and enthusiasm in a congested part of the field. Combined with Cleverley to good effect.
United fans are still optimistic that the midfielder can reach his full potential at United if he can stay injury-free.
Ashley Young: 6
The English left-winger put in an energetic shift Monday night, but failed to really create anything meaningful in a packed midfield.
Withdrawn for Robin van Persie on the hour.
Danny Welbeck: 7
Danny Welbeck is quickly becoming a very useful player in attack for Sir Alex. Against Reading, he held the ball up well and harried the opposition when not in possession.
He does need to become more clinical in the final third, though, if he is to continue to earn a berth in the starting XI.
Javier Hernandez: 7
With Welbeck currently playing the better football, Hernandez is unfortunately slipping down the Old Trafford pecking order.
But his well-taken goal may have reminded Sir Alex that he has four top-class strikers at his disposal capable of influencing a game for the good.
The Portuguese winger immediately looked dangerous after coming on late in the first half, striking two powerful efforts that went close.
Was the difference-maker who scored United's first and a genuine contender for man of the match.
Robin van Persie: 7
The Dutchman brought class and composure to the game and helped push the Red Devils over the line with his quality.
Michael Carrick: N/A
Carrick helped steady the ship during his 10-minute cameo.
How would you rate United's players?