United stormed up the other end with van Persie freeing Evra and meeting the Frenchman's cross on the full, only for Stamatoupolos to pull off an amazing save.
There was disappointment when Nani pulled up sharply with a groin injury and was subsequently withdrawn, but Henriquez was afforded a first opportunity to impress David Moyes, initially in a left-wing role before switching flanks with Zaha.
AIK finished the half strongly with Ibrahim Moro, Igboananike and the lively Kayongo-Mutumba all registering attempts on Lindegaard's goal but failing to prevent the teams entering the break all-square at 0-0. The hosts continued to press after the restart and took the lead when Alhassan Kamara's flick allowed Quaison to turn past Nemanja Vidic and curl an unstoppable finish past substitute Ben Amos.
Vidic had to be alert to prevent Robert Ahman Persson storming through on goal soon afterwards and almost levelled himself when rising to meet a Ryan Giggs corner, only to see his downward header bounce up against the bar. Yet the Reds still had to contend with some near-misses at the other end with Bahoui's Ronaldo-esque free-kick going close to doubling the lead. Evans was forced to hobble off with Chris Smalling taking his place which must be a concern to boss Moyes.
Henriquez moved into a central position and was at the heart of most of the initial attempts to retrieve the situation, being foiled by substitute keeper Patrik Carlgren on one occasion. The 19-year-old United striker, who finished last term on loan at Wigan, was not to be denied and levelled with a poacher's finish, side-footing home from close range with his left foot after Zaha had collected a Michael Carrick pass and drilled over an inviting centre.