You can find out how the match unfolded with our minute-by-minute commentary below.
Man United: Lindegaard, Ferdinand, Carrick, Giggs, Nani, Kagawa, Van Persie
Reading: Andersen, Gunter, Pearce, Carrico, Guthrie, Robson-Kanu, Pogrebnyak
"I'm used to playing games every few days," the Daily Mail quotes him as saying. "I like it because I get into a rhythm.
"When you don't play for more than a week, it can take you 10-15 minutes to start because you're missing that rhythm. I prefer to keep going, to keep playing game after game.
"The incentive’s there to get to the quarter-finals. I don’t think that will be lost on the players, no matter what side I pick," he said. "We’re taking nothing for granted. With an FA Cup tie you always have to expect the unexpected. It happens so many times, you just don’t want to be a casualty or a shock.
"For many people, it’s Reading and they think ‘Yeah, we’ve just been to Madrid, it was a great night and this will take care of itself’. It can’t take of itself. We have to take care of it. We must have a performance that respects our opponents and the fact the FA Cup can produce shocks.
"We’ve suffered them ourselves and we don’t want another one. I went to see Reading last week and they’re a team showing plenty of fighting qualities, as you’d expect being down the bottom part of the league."
"That attitude comes from the manager and the ingredients he puts into the mix," he said. "Sir Alex has an incredible will to win and you can see that from the way he is on the touchline.
"Whatever he puts into the game, they never feel like they are beaten. We're trying to get that too. Luckily we have had that over the last few years. We've kept going in the last few games particular."
"You see the results in the last round and this weekend, who would think Blakcburn would win at Arsenal? The Cup can make things happen.
"Every game is a selection dilemma. All the big games are cropping up and it's not easy but I have to pick the right team."