The Manchester United manager gave his 35-year-old striker a rest for the visit of the Tigers as Mourinho started with Marcus Rashford and Wayne Rooney up front.
However, the 20-time English champions struggled make the breakthrough against the relegation candidates in the first half despite Henrikh Mkhitaryan starting behind Rashford and Rooney.
The Armenia international did tee up Juan Mata to make the breakthrough in the second half after the midfielder nodded the ball into the Spanish midfielder’s path for the opener.
Marouane Fellaini added a second in the dying moments of the first leg after Matteo Darmian’s superb cross.
Former Arsenal and West Ham striker Hartson highlighted Ibrahimovic’s absence after Manchester United’s unimpressive 2-0 win against the Tigers.
United showing so far how important Zlatan is and has been for them.. focul point and gives them a presence in final third. #zlatan
— John Hartson (@JohnHartson10) January 10, 2017
Manchester United will host Liverpool in their next Premier League game at Old Trafford on Sunday afternoon.
The Red Devils are in sixth place in the table.
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