Harry Maguire scored a controversial stoppage-time winner as FA Cup holders Man United fought back from a goal down to beat Leicester City and advance to the fifth round.
With extra time and potential penalties looming, Bruno Fernandes sent a free-kick into the box and Maguire headed home.
The defender appeared to be offside, but with the video assistant referee (VAR) not used at this stage of the competition, it was not picked up by the officials and the goal stood.
It was some much-needed joy for Man United fans, who had seen their side beaten at home in five of their past seven games at Old Trafford.
They will have likely feared the worst after Leicester took the lead towards the end of a largely dull first half, with Bobby De Cordova-Reid heading in after Andre Onana’s save from Wilfred Ndidi’s strike bounced up kindly for him.
But Man United were much improved in the second half, aided by the introduction of Alejandro Garnacho.
He caused Leicester numerous problems with his runs and it was from his cross that the hosts got the equaliser, finding Rasmus Hojlund, whose shot was blocked but Joshua Zirkzee was on hand to sidefoot home moments after coming on.
From then on the Red Devils looked the most likely to grab the winner, and so it proved with Maguire’s header in the third and final minute of stoppage time – though Leicester fans will feel aggrieved that it stood.