Andriy Yarmolenko curled in the opener for the Hammers on the stroke of half-time, before Aaron Cresswell's free-kick secured all three points for the Hammers with six minutes to spare.
United had two great opportunities to draw level in the second half, as Juan Mata put the ball wide from close range, while Harry Maguire had a powerful strike parried away by Lukasz Fabianski. The Reds were dealt a further blow, as Marcus Rashford had to be withdrawn due to a groin injury.
Speaking to MUTV and in his post-match press conference, the Norwegian delivered his assessment of the match and provided an injury update ahead of another busy week of fixtures.