Early in the second period, Schlupp somehow headed Adnan Januzaj’s wicked in-swinging free-kick wide, before Sama was sent off for a second bookable offence following a robust challenge on Lingard.
Larnell Cole spurned another good chance as United took control, shooting wide with the outside of his right foot after chesting the ball down nicely inside the box. Schlupp then fizzed a shot into the side-netting from distance and saw yet another effort parried wide.
With 20 minutes left, skipper Tom Thorpe had a header cleared off the line and, moments later, Lingard drove inches wide from 20 yards.
After Amos made a comfortable save from Joao Teixeira in his first action of the second half, Suso fired a decent chance just over as the hosts threatened to snatch the points.
Ten minutes from time, Büttner’s deflected drive landed on the roof of the net, with Ward scrambling. At the other end, Amos produced a superb save to deny Suso from distance.
And at the death, Fornasier poked home after a goalmouth melee to hand United a second win the Elite Group, to add to a draw and a defeat.
United: Amos; Veseli, Thorpe, Fornasier, Büttner; Lawrence (Ekangamene 50), Powell, Cole, Lingard; Januzaj (Blackett 76); Schlupp. Subs not used: Gollini, McGinty, James.