Brady was injured and replaced soon afterwards, with Henriquez also taking a breather after being given a harsh lesson in English football for much of his evening. Home substitute Noble, who scored four goals in this fixture last year, had a chance to win it after wriggling his way through but the ball looped off Johnstone and drifted wide.
United's final effort came when Petrucci rolled a free-kick into Tyler Blackett's path but the substitute's fierce shot flew wide of the target.
United: Johnstone; Veseli, Fornasier, Thorpe, Brady (Blackett 66); Ekangamene, Cole, Petrucci; Macheda, Henriquez (James 74), King. Subs not used: Gollini, McCullough, Hendrie.