The forward brought the ball down on his chest in the area, before turning and knocking it past David De Gea just seconds before the break.
The Reds piled on the pressure in the second half and were unlucky not to grab a late equaliser when substitute Mason Greenwood hit the post.
You can watch the highlights from the game at the top of this page and scroll down to see post-match reaction from Ole Gunnar Solskjaer and Harry Maguire.
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