Marcus Rashford scored the all-important winner with virtually the final kick of the game, ghosting in at the back post to tap in Edinson's Cavani's low cross. The substitute provided much-needed impetus when he came on in the second half, and made the difference.
Harry Maguire made a positive return, and made a string of key tackles to keep Michail Antonio quiet. In the first half, when West Ham launched a threatening counter attack, Maguire marshalled the striker well and made a well-timed tackle to keep the score level.
Diogo Dalot put in yet another strong defensive display, as he continued his development into a key member of the United squad.