Substitute Javier Hernandez came up trumps with a late equaliser at Liverpool to earn a precious point for the champions.
United were forced to come from behind and battle hard for a point after Steven Gerrard broke the deadlock with a free-kick and Chicharito's predatory header after Danny Welbeck headed on a Nani corner meant a lot more than his consolation at Anfield in last season's fixture.
The manager sprung a few surprises with his team selection with Wayne Rooney and Nani left on the bench, Phil Jones playing in midfield and Danny Welbeck starting in a lone attacker's role. Skipper Nemanja Vidic missed out despite representing Serbia in midweek.
There were a lot of misplaced passes in a frenetic first half with neither side really able to stamp too much influence on the proceedings. United's first glimpse of goal came after a quarter of an hour when Welbeck's positive play eventually led to Patrice Evra crossing from the left and Phil Jones heading into the side-netting.
The Reds limited the chances at the other end but Gerrard's dangerous cross evaded everybody in the middle before the clearest opening of the first period came on 35 minutes. Charlie Adam's shot bounced kindly into the path of Luis Suarez, who turned Jonny Evans but could only shoot straight at David De Gea, who made a vital save. Darren Fletcher and Ji-sung Park were off target with speculative efforts as Sir Alex will have been pleased with his side's contribution to a tight opening 45