United's lead at the top of the table was trimmed to five points after a shock 1-0 defeat at Wigan.
The reigning champions failed to take another step towards a record 20th title in a controversial encounter but, in truth, the relegation-haunted hosts deserved to take something from the game with two major talking points set to dominate the post-match discussion.
Assistant referee Dave Richardson flagged to rule out a Victor Moses header in the first half and denied the Reds a blatant penalty with 18 minutes left when failing to spot Maynor Figueroa clearly handling a Phil Jones cross. Shaun Maloney's excellent strike five minutes into the second half was enough to hand Wigan only a third league win at the DW Stadium all season and wreck United's 100 per cent Barclays Premier League record against Roberto Martinez's men.
The Latics dominated much of the first half and were aggrieved not to be ahead at the interval. On the half-hour mark, Maloney's corner was headed home by Moses but the effort was disallowed for a foul by Gary Caldwell on David De Gea. The defender was obstructing the Spanish keeper after getting goal side of Jonny Evans but there was relief that an offence was spotted by the assistant referee Richardson.
Phil Dowd did seem a little quick to award free-kicks in general, with the home players going to ground pretty easily - particularly Franco Di Santo - and a booking for Evans after the slightest of touches on the former Chelsea forward was extremely harsh.
De Gea palmed over a James McCarthy shot and Moses had a hopeful penalty shout rebuffed when driving the ball against Jones as the Reds struggled to make any impression. Ryan Giggs forced a corner after a long-range one-two with Michael Carrick but the first attempt of note from the