The Swedish striker arrived at Old Trafford on a free transfer from PSG last summer and many questioned whether he would be able to cut it in the Premier League in the latter stages of his career.
However, the 35-year-old has more than proved his worth at Manchester United and has already scored more than 24 goals for the Red Devils so far this season.
Mourinho worked with Ibrahimovic during the pair’s time together at Inter Milan, but the Portuguese coach admits that he was not surprised by the way in which the striker has adapted so well to life at Old Trafford.
Speaking to BBC Sport, Mourinho said: “Zlatan is not a surprise for me.
“I know the personality, I know the body, I know the ambition that brought him here.
“Could he do it in the best league in the world? He has done it everywhere else. He’s doing amazingly well.”
Ibrahimovic will not feature for Manchester United for the Premier League trip to Middlesbrough on Sunday afternoon due to suspension.
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