The away side dominated from the outset with Jesse Lingard testing Jordan Pickford with a well-struck shot from the edge of the box.
Sunderland barely touched the ball in the opening half and they finally fell behind when Ibrahimovic was allowed to turn near the left-hand edge of the box and the big Swede fired a a fierce low shot past Pickford.
The home side then fashioned their best chance of the match when Victor Anichebe controlled the ball and forced Romero in an excellent close-range block.
Manchester United fans react on Twitter to starting XI against Sunderland
Sun, April 9, 2017
Manchester United fans can't believe Jose Mourinho's starting line-up set to face Sunderland at the Stadium of Light (1.30pm)
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Manchester United fans are struggling to cope with the team to face Sunderland
Manchester United's Zlatan Ibrahimovic celebrates scoring
But David Moyes' side went down to 10 men in the 43rd minute when Seb Larsson received a straight red card for a challenge on Ander Herrera.
Then just 47 seconds after half time, Sunderland went to 2-0 down.
The returning Luke Shaw passed to Mkhitaryan and the Armenian fired into the bottom corner.
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