Middlesbrough head coach Aitor Karanka has warned his players not to be fooled into believing they can succeed at Manchester United just by stopping Zlatan Ibrahimovic.
Ibrahimovic, 35, has scored 17 goals in all competitions, with 12 in the Premier League, since joining United on a free transfer in the summer.
Karanka, who was Mourinho's assistant at Real Madrid, knows his side will have to limit the Swede's opportunities but said United have many more threats.
He said: "He is one of the best players in the world. He is still young even when he is 30-and-I-don't-know-how-many-more.