Mata’s future has been in question after he was frozen out by Mourinho at Chelsea, eventually selling the player to United. Mata was also subbed off, despite being a substitute himself, during last Sunday’s 2-1 win over Leicester City in the Community Shield.
“One thing is the stories people write. The other thing is the reality,” Mourinho told Sky Sports. “Seeing what happened in our previous club, people thought he had no future. It is completely different.
“I trust him. Every time he plays, I know what he can give and I know what he cannot give. He has a lot to give.”
Mata repaid his manager’s faith in him by putting Man United in front in the 40th minute.
The United manager, though, denied there is a pecking order and says he judges his options week by week. The Portuguese explained: “We have a very good group with lots of options. It is difficult to say that ‘this player’ is more important than ‘this player.’ I analyse in the week.”
Discussing Jesse Lingard’s absence, he added: “Lingard is injured. He couldn’t recover from the Community Shield. We tried but it was not possible.”
With Paul Pogba suspended, Ander Herrera start at Dean Court alongside Marouane Fellaini.
Mourinho said: “Herrera has been working since the first day of preseason. He has had 33 training sessions and minutes in every match. His condition is very good.”