save from Federici, who first pushed away Tom Cleverley's low effort, then brilliantly plunged to his right to somehow turn Young's follow-up around the post.
That brief flurry of activity was out of keeping with a pedestrian opening half which was unfortunately most notable for the withdrawal of Jones, who was left limping heavily after a crunching, 50-50 challenge with McAnuff.
The defender was replaced by Nani, who quickly provided the outstanding moment of the half with an outrageous first-time volley which thudded off Federici's right-hand post.
Clearly keen to impact on proceeding, the Portuguese then forced Reading's Australian stopper into action with a vicious, dipping left-footed effort which was only just pawed over the bar in the final act of the half.
The upsurge in tempo carried over into the second half, with United's approach full of vim and vigour, yet once again quickly faded out in the face of Reading's physical, resolute approach.
Nemanja Vidic's heavily deflected header needed to be cleared off the line by Noel Hunt, Federici comfortably parried away Anderson's right-footed effort and Nani scuffed a shot narrowly wide as United gradually cranked up the pressure.
By the time the Portuguese arrowed another left-footer wide from distance, Robin van Persie had been introduced in place of Young as Sir Alex Ferguson sought to stave off the growing spectre of a replay. Sure enough, the dam broke with 21 minutes remaining.